|“||Life is a book, and there are a thousand pages I have not yet read. I would read them together with you, as many as I can, before I die—||”|
William "Will" Herondale was one of the wards living in the London Institute whose life became entangled with that of the newly-arrived Tessa Gray. Will went on to become the head of the Institute and father to James and Lucie Herondale.
Will was the son of Edmund Herondale, a former Shadowhunter, and Linette Owens, the mundane woman whom Edmund left his Shadowhunting life behind for. As dictated by the Nephilim Law, Will and his sisters, Ella and Cecily, being Nephilim, were still welcome to rejoin the Shadowhunter ranks.
Per Shadowhunter protocol, Will, during the first twelve years of his life, was asked twice to join them. He refused both times, having been raised to believe that Shadowhunters were not good people and that the lives they led were dangerous and monstrous. However, shortly after the second time he was offered, Will went through his father's old things and found the Pyxis that held the Greater Demon Marbas and opened it, unwittingly unleashing the demon. Will was attacked by Marbas but was protected by his older sister, Ella, who was subsequently poisoned by the demon. Before it left, Marbas claimed to have placed a curse on Will, telling him that those who love him would die unless he left their lives forever. When Ella died the next morning, Will was wracked with guilt and sorrow, believing himself to be responsible. Will then immediately decided to leave and join the Shadowhunters at the London Institute to keep his family safe.
Even in London, Will was haunted by the demon's curse. Will remained distant from and cruel to the other inhabitants of the Institute, Charlotte and Henry Branwell, not wanting to bring harm to them by becoming attached and having them love him. This held true even for guests at the Institute. When he was twelve, an Enclave Christmas party was held at the Institute. There, he found the diary of Tatiana Lightwood, a young Shadowhunter who was greatly infatuated with Will. Will proceeded to humiliate Tatiana by reading her poetry for him out loud at the party, earning the spite of Tatiana's brothers, Gabriel and Gideon. He was attacked by Gabriel for it and, despite his own lack of training, Will bested him in the fight and even broke his arm, further humiliating Gabriel. This instigated the beginning of a long rivalry between the two.
When Jem Carstairs arrived from Shanghai in 1873, Will tried to be rude to the boy to immediately dissuade him from trying to befriend him. However, Jem refused to be intimidated by Will and insisted on training with him. When Will learned that Jem was ill, Will allowed himself to become close to the other boy. Will convinced himself that since Jem was already dying, the curse would be worthless against him, making him Will's "greatest sin". When they were thirteen, Will asked Jem to become his parabatai, and when they were fourteen, they underwent the ceremony.
Tessa and the Magister
After a routine patrol led Will and Jem to Emma Bayliss in 1878, they had since been on the trail of the Pandemonium Club, the suspected orchestrators of her murder. Their investigations led them to the Dark Sisters. On the evening they were supposed to catch the sisters for their illegal activities, Will found a girl, believed to possibly be a warlock, named Tessa Gray imprisoned in their house. They rescued her and took her back to the Institute.
Will developed an attraction towards Tessa and the pair bonded over their love for books. Will had to constantly remind himself to keep his distance due to his curse.
While the Shadowhunters of the London Institute continued to investigate the Pandemonium Club, they also started looking into Tessa's brother's whereabouts, as she had been told he was imprisoned by the Dark Sister's as well. This brought them to Axel Mortmain, his employer who was seemingly tied to the Pandemonium Club as well. He told them of the Pandemonium's head, who was known as the Magister, which was apparently the vampire Alexei de Quincey. At a reconnaissance mission at a party of de Quincey's, Will accompanied Tessa, who had Changed into the vampire Camille Belcourt, and pretended to be her human subjugate. When he saw de Quincey's violations against the Accords, Will tried to alert the other Shadowhunters with one of Henry's prototype inventions, but instead set fire to the curtains; though it alerted the Shadowhunters, it also caused panic among the attendees. A fight soon broke out and though many of the vampires were defeated, de Quincey managed to escape.
While fighting de Quincey, Will bit the vampire. Because of the vampire blood he had ingested, Will was subjected to a purging remedy to prevent him from becoming a darkling; he was forced to drink holy water to help dispel the vampire blood in his system. When he began to violently refuse Sophie's assistance, Tessa replaced her and brought him holy water. After a short conversation about what they thought of each other, they kissed passionately before Will regained his senses and broke away, putting his walls back up.
On the night of the Clave's attack on de Quincey's hideout, Mortmain went to the Institute to warn them that the Dark Sisters were planning on animating the Magister's clockwork army. Will and Jem rushed off to stop them, tricked into leaving the Institute unprotected. When they arrived at the location Mortmain reported, they only found Mrs. Dark conducting a necromantic ritual to bring her sister back to life. After killing her and realizing that Mortmain had deceived them as he was in fact the Magister, Will rushed back to the Institute on Balios, leaving Jem behind with Xanthos to pull the carriage.
Will found Tessa on the floor of the Sanctuary, bleeding out, with Mortmain next to her, who was surprisingly upset. Mortmain fled after being confronted by Will and Will moved to hold Tessa, visibly upset at her death, though after a moment he realized she was breathing. Tessa opened her eyes and explained to Will that she tricked Mortmain into believing that she had stabbed herself. Will, however, was still distraught as he believed that he had lost everything.
Afterward, Will feared he had endangered Tessa with his curse and she had clearly been able to see his feelings when he thought she was dead. Deciding he needed to crush any care she may feel for him, he told her that they should have a sexual, uncommitted arrangement as he could not possibly have a future with a warlock. He especially hurt her by revealing the fact that warlocks are sterile.
Breaking the curse
Realizing he could not take her hatred or a life without her, Will went to Magnus Bane for help in breaking the curse. Magnus agreed to help Will in exchange for him owing Magnus a favor. Will agreed and Magnus set to work trying summoning countless blue demons, hoping they'd be the right one—which they never were.
Meanwhile, the Institute was working on tracking down Mortmain. After a suggestion from Jem, they managed to turn up an old Reparations request filed by Mortmain against the York Institute for the murder of his parents. Tessa accompanied Will and Jem, up to the York Institute to meet Aloysius Starkweather and get the full report from his files. While investigating the house listed on the report, Will found his family was living there. Upset, Will nearly charged straight up to them but was held back by Jem and a threat from an automaton if he did.
When they returned to London Will, still rattled from having seen his family, took off. He first visited Magnus and demanded he send him through to the demon realms. After Magnus refused and told him to sleep it off, Will stormed out and went to an Ifrit den. When Jem finally located Will, he ended up punching him in the face out of frustration and anger that Will had made a mockery of the drug that was killing him. Will had never made Jem so angry and begged for his forgiveness when Tessa explained it to him the following day.
That night, Sophie found out that Jessamine had been in contact with Nate and had an invitation to a masked ball at the Lightwood's house. She told Tessa who went to Will for help. Because of the urgency as the party was taking place that evening, Will immediately set to go on the mission himself, with Tessa by his side. Tessa Changed into Jessamine and Will snuck into the party, blending in with his mask.
Will carefully watched Tessa during the time she interacted with Nate to get information. Later, on the balcony at Benedict Lightwood's estate, Tessa and Will shared a long, passionate kiss that was interrupted by Magnus Bane, who informed them that they have been under the influence of warlock powder. He then helped them leave before anyone else could recognize them. While in the front garden of the house, however, Will spotted the demon that had cursed him and chased after him.
After chasing the demon all around London, Will went to Magnus's house with a tooth the demon had left in his arm. With this, Magnus was able to summon the demon Marbas in order for him to release Will from his curse. However, Marbas told them that there was no curse in the first place, that it had been a trick he'd played on him. He told Will that Ella had in fact died because she was wounded from his stinger. Will was distraught but went back to the Institute, giddy with happiness and excitement to profess his love for Tessa. His happiness was short-lived as Tessa told him that she had become engaged to Jem. Will, heartbroken, told Tessa not to tell Jem about his feelings and pretended to be happy about the engagement for Jem.
Saving Jem and Tessa
Not long after, Will told the rest of the Institute of his "curse" and why he had been so cruel to them in the past. He also began training his sister, Cecily, who had recently arrived at the Institute, to become a Shadowhunter. However, he was annoyed at her presence in the Institute and her insistence on him coming home with her. Still, he clearly cared for her and was fiercely protective of her.
A couple months later, the Institute was visited by Gabriel, covered in blood and asking for his brother. When Gideon came, Gabriel explained that their father had turned into a giant demonic worm in the final stages of his Demon pox. The group set out to Lightwood house and dispatched of him, but not before he had killed the servants and Tatiana's new husband.
After Jem's collapse following the battle, Will discovered that Jem had been taking large doses of yin fen to keep him fit and able, which was simultaneously killing him inside at a quicker rate. He traveled to buy more of the demon powder, with Cecily who followed him, but soon discovered that Mortmain had bought it all up. They then received a letter from Mortmain offering them yin fen in exchange for Tessa. Before anyone could stop him, Jem seized the note and the small packet into the fire, which resulted in Will diving into the flames to retrieve some of the drug.
A few days later, Jessamine Lovelace was returned to the London Institute after having been in the Silent City's prison. The Magister's automatons followed the Silent City's carriage inside the gates and began to attack. After feeling Magnus's necklace pulse, Will rushed outside to join in. There he saw Jem run through the gates and Jessamine trying to crawl to safety. Will carried Jessamine out of the battle before realizing that she had been stabbed in the back. Before she died, Jessamine told him that Mortmain was in Idris and that he was a terrible Welshman. Jem returned right after, having chased the carriage that took Tessa until he lost it, and collapsed.
Cecily overheard Will's conversation with Jessamine and figured out that Mortmain was hiding in Cadair Idris, a mountain near where Will used to live in Wales, as she knew Mortmain and his personality. They sent word to the Consul but he refused to act on the lead, leaving Will torn between going after Tessa himself and staying with Jem.
Instead, Will sent for Magnus to help them find a cure for Jem, who was dying and out of yin fen. While the two were in Jem's room, Jem overheard Magnus ask Will if he had told Jem that he loved Tessa. When Magnus left, Jem asked Will of it, to which Will had to confess. Jem then gave Will his blessing and asked him to rescue Tessa, as he could not. Will left immediately.
While at the Green Man Inn, on the road to Wales, Will felt his parabatai bond snap and saw his rune bleeding. Realizing that Jem had died, he went insane with grief and, feeling he had nothing left to lose, seriously wounded and killed some werewolves when they tried to attack him. Woolsey Scott broke up the fight and offered him the advice that he should still try to live as Jem would have wanted, rather than give up. Later, while still riding toward Cadair Idris, Will cut his hand with Jem's dagger and buried it in the ground by a tree to commemorate their unbreakable bond.
Eventually, he found Tessa in Mortmain's hideout. However, he became trapped inside with her after passing through an invisible barrier. Will then broke the news that Jem had died. Racked with grief and thinking that they would both die, Will confessed everything to Tessa how much he loved her. She asked to kiss him one last time, which lead to them to have sex that night. The angel inside Tessa's necklace subsequently left a star mark on Will's shoulder, to mark him and his lineage as someone special to the soul he was bound to.
The next morning, Magnus Bane found them and released them, bringing them to where the others were battling against hundreds of automatons. Will joined the battle right away and, in the midst of the battle, found out that one of the Silent Brothers, Brother Zachariah, was actually Jem. Tessa was then captured by Mortmain, once again, who threatened Will and the other Shadowhunters with her. Tessa Changed into the angel trapped inside her necklace, Ithuriel, leaving Will in awe as he watched her blaze with fire and killed Mortmain. She then fell to the ground unconscious, slowly turning back into herself and bleeding Ichor, and worrying Will.
Much to his relief, Tessa soon recovered and he was allowed to converse with Jem and have a true farewell. Though this made him feel gloomy for weeks but he gradually started to recover and adjust to a life without Jem. Over the coming weeks, Will and Tessa grew closer and, with the encouragement of Jessamine's ghost, became engaged during the Enclave's Christmas party.
In a trip secretly sanctioned by Charlotte, Will, Tessa, Cecily, and Gabriel went to Ravenscar Manor using Henry's Portal, finally reuniting with his parents. During the trip he got to explain why he left and introduce his parents to his fiancée. This would not be his only trip back home, however. Over the years he visited them for holidays and other special occasions.
Institute head and fatherhood
Eventually, Will became the head of the Institute, a position Charlotte passed onto him as part of her condition in accepting the Consul post. He and Tessa eventually wed and, years later, unexpectedly had two children: James and Lucie Herondale.
Over the next 25 years, the Shadowhunters of London lived in relative peace as demon attacks became less and less frequent until they became so scarce that patrols seemed unnecessary. Though this should be cause for rejoicing, knowing that the children of this generation he cared so dearly for were not in imminent danger, it made Will worried that when war did come, they would be unprepared.
And of course, war did come and Will was unfortunately right. In 1903, London was plagued by a Mandikhor demon and its Khora demon offspring that were impervious to sunlight and brought down a poison the Shadowhunters had no cure for. Will attended and held countless meetings throughout the time of the attacks but found himself struggling to get the Enclave to take proper action, even when placed under quarantine.
The poison ended up taking the life of Gideon's daughter, Barbara Lightwood, and Will's whole family grieved. Though Will firmly believed in his nephew's attempts at finding an antidote, Christopher soon became ill as well, troubling the family even more. And, despite Will's best efforts, his son wound up in the middle of the battle, eventually taking down the demon and facing down his grandfather, Belial, who was behind the attacks.
While London celebrated James and his friends as heroes, Will held a final meeting to discuss the whole ordeal with the Consul. The meeting was derailed, however, by Tatiana Blackthorn's wild accusations that James had orchestrated the attacks and burned down Blackthorn Manor. Will stood up for his son but was shocked by the confession of Cordelia Carstairs that James had been in her room the night of the fire. In private, Will began to reprimand James for his mistreatment of women before he was cut off with the news that James and Cordelia were engaged. Will was then elated that the Carstairs and Herondales would be more closely bound.
In December, Will and Tessa hosted James's wedding at the Institute. Shortly before the wedding, Will advised James to always tell the truth to his future wife, despite how hard it might be, as well as informed him of Elias's unexpected arrival and his duty to stand by Cordelia. At the reception, he helped distract the guests from Elias's outburst and subsequent removal from the room. He and Tessa gifted the newly weds a house on Curzon Street, a carriage, and Xanthos—as Cordelia had taken to feeding him carrots so Will believed the horse had a high opinion of her.
A couple of weeks later, he and his wife left for Paris to help resolve an issue there. Charles—who had been stepping in as the temporary head of the Paris Institute—had forgotten to invite the vampire clan from Marseillaise to a meeting of the vampire clans of France. The clan took offense, thinking it to be intentional, especially as Charles did not apologize. Will and Tessa stepped in to prevent a war since they were trusted and respected in Downworld. They brought the Mortal Sword as a show of good faith and honesty.
Once matters were resolved, they were summoned back to London as Thomas was accused of being a serial killer and needed to give testimony by the Sword. In the Sanctuary of the London Institute, Will conducted the investigation, supervised by Charlotte and Inquisitor Bridgestock. After Thomas was proved innocent, Leviathan attacked the Institute while trying to cross into the world and he fought alongside his family and friends. After the battle, James returned to the Institute with a story to explain the murders and what had happened in the courtyard—though Will knew it was not the full truth. From Brother Zachariah, Will received a message from Charlotte saying she was giving Will the power to investigate further into the situation, which he decided to begin the next day and dismissed everyone.
That night, he was resting with Tessa when Jessamine informed both of them about Lucie's necromantic abilities. Though he did not believe it at first, Will went to check on her and found her missing, along with a note saying she and Malcolm were going to try to resurrect Jesse Blackthorn. He sought Magnus's help and rushed off to catch James just before he got on a train for Paris with Matthew and Cordelia—for his honeymoon as James claimed. Will requested he help them find Lucie as she would listen to James and they sped off to Cornwall on Lucie's trail; Will swearing to get the rest of the story from James and Magnus on the way.
When Will retired, he went on to write several Shadowhunter histories which became very well-known and respected.
In 1936, 8 months before his passing, Will and Jem were granted a vision by the Greater Demon Belial. The two of them were able to see each other in a dreamland-type place where they were young children again and free of any of the things that had always tied them down. The illusion was in Jem's birth city, Shanghai, as Jem had long wished to go with him and they were able to spend a few hours simply together and happy one last time.
In June 1937, Will, at 76 years old, died of old age. On his deathbed, he was visited by their friends and family, and, finally, Jem, as Brother Zachariah, who came and played him the violin. Jem bade him the Shadowhunter farewell, and Will then died surrounded by the two people he loved most in his life: Tessa and Jem.
Though Will never returned to the world as a ghost—having died happy and with no unfinished business—Magnus Bane strongly sensed that Will had yet to cross over into what lay beyond, and was instead waiting by a dark river for Jem and Tessa to join him so that they may cross together.
In 2010, Will was able to bridge the thin divide between dreams and death to temporarily be present for Tessa and Jem's dream wedding. There he congratulated the pair and shared in their joy as seeing them together brought him great peace.
Will is a caring, affectionate man who would risk his life and happiness for the people he loves.
In his youth, when Will's instinct had been to push people away, Will kept his good traits hidden behind arrogance and sarcasm. To those who didn't know him, he came across as rude, childish, and egotistic, with his quick wit and sarcasm. As an adult, Will became openly kinder and considerate. Even in serious situations, Will kept his same jovial and good-humored attitude. He was also a great leader and a clever and strategic thinker.
Will reads extensively and has an exceptional memory. He can find a quote for almost any situation and often makes his own (very bad according to even his friends and family, although sometimes purposefully) poetry.
Will has black hair and blue eyes, often described as the color of a pansy, with long, thick eyelashes. He has high cheekbones, full lips, and is described as extremely handsome by most people. He is said to greatly resemble his mother. He is muscular and well-built with broad shoulders and callused hands from his years of training as a Shadowhunter. He is also quite tall, standing at five foot ten.
Will has a tattoo of the Welsh Dragon on an intimate spot on his body. Will's parabatai rune is on his chest, over his heart. When he was married, one of his marriage runes was placed on his chest, as per tradition, and ended up next to his faded parabatai rune.
Skills and abilities
- Nephilim physiology: Being Nephilim, Will possesses a variety of enhanced physical and mental abilities granted to him by the blood of Raziel in his veins and also by the angelic Marks of the Gray Book. He also has the power to perform tasks unique to their species, such as the ability to use and call on the power of the angels for their seraph blades. This includes enhanced strength, agility, stamina, and coordination, which only improves over time and practice.
- Runic magic: Due to the angel blood in their veins, all Shadowhunters are able to apply runes on their skin without any real danger. These Marks, in turn, give varied effects that serve to benefit the wearer.
- Marksmanship: Will is particularly adept at knife throwing, a skill perfected with the help of his parabatai, Jem.
- Parabatai bond: Due to his past parabatai bond with Jem Carstairs, Will was able to call on more strength in battle. The runes drawn on him by Jem also gave a considerably stronger effect.
- Daggers and throwing knives: Will's primary fighting method aside from seraph blades.
- Herondale dagger: One of the only things Will brought with him when he left home was a dagger, given to him by his father, with the markings of herons on the blade.
- Other basic Shadowhunter gear, including: steles, seraph blades, and a witchlight.
- Wedding ring: Will and Tessa's wedding ring has a design of herons on the front and an etching of a lightning bolt on the inside to represent Will and Tessa's Shadowhunter heritage respectively. The words "the last dream of my soul" were also engraved inside, a reference to A Tale of Two Cities.
|“||I felt I was dreaming and thinking and feeling with you. I dreamed what you dreamed, wanted what you wanted—and then I realized that I truly just wanted you. The girl behind the scrawled letters. I loved you from the moment I read them. I love you still.||”|
–Will to Tessa, Clockwork Prince
Will first treated Tessa as he did everyone that wasn't Jem: rudely, to immediately establish a distance between them because of the curse he thought he had. Will inevitably took a liking to Tessa, especially after reading the letters she'd written for her brother Nate, where Will seemed to get to know Tessa's character before even spending time with her. The pair grew somewhat close because of Tessa's persistence on helping and getting to know him, and though Will tried to fight it because of the curse, he realized that he had developed feelings for Tessa. For the first time in so long, Will wanted to be close to someone enough to look for a way to break his curse.
While he was still uncertain about what could be done about his curse, Will continued to push Tessa away, going as far as propositioning her to offend her and dampen her feelings for him. However, when he realized that he was never cursed, Will immediately told Tessa and confessed his love for her, only to find out that she had just gotten engaged to Jem. Will decided to set aside his own feelings, wanting the two people he loved to be happy.When Will thought that Jem had died, and when they thought that they were about to die soon, Will and Tessa slept together. When they survived the ordeal, Will and Tessa became part of each other's recovery, supporting each other in light of their loss of Jem. Will made an attempt to court Tessa properly and gave her the A Tale of Two Cities book in which he'd written a letter for her. Will was afraid that Tessa wouldn't love him the way she loved Jem but, egged on by Jessamine, he eventually proposed to her. The couple soon tied the knot and had two children, Lucie and James.
|“||You hear that, James Carstairs? We are bound, you and I, over the divide of death, down through whatever generations may come. Forever.||”|
When Jem arrived at the London Institute, he and Will immediately became friends after he showed that he was not intimidated by Will's moody attitude. When Will learned that Jem was dying, he believed the curse wouldn't affect him, and each passing day since has solidified that theory, though he still considered Jem his great sin. The two soon became like brothers and when they were 13, Will asked Jem to be his parabatai. Jem refused, but Will put a bet on a sword fight and bested him, making him agree. They went through the ceremony a year later.
Before Tessa, Jem was the only person Will truly cared about and showed affection to. It is said that Will spent a lot of time in Jem's room, ensuring that he wouldn't die because of his yin fen addiction. Will even took to buying Jem's yin fen for him from the ifrit's den in Whitechapel because Jem can't face it.
When he found out that Jem loved Tessa and was engaged to her, Will sacrificed his love for her and tried to be happy for them. Believing it to be his burden, Will hid his feelings from Jem. However Jem eventually found out and, despite his worst fears, Jem was relieved instead of angry. He asked Will to go save Tessa, be with her, protect her, love her and keep her happy, for he couldn't do it himself.Jem then left and became a Silent Brother, leaving Will heartbroken and he fell into depression for months. When he finally recovered, Will was insistent on keeping him as a part of his and his family's life, often calling on "Brother Zachariah" for minor or nonsensical things. He even had his children James—who he had named after Jem—and Lucie refer to him as Uncle Jem.
Charlotte always treated Will with almost maternal love and care. Because of his believed curse, Will maintained a semblance of indifference towards her, as he did with everyone else. But Will did in fact care for her, choosing to keep his distance to protect her. When he learned the truth of his curse, Will told Charlotte that he was grateful for all that she had done for him and as repayment he wasn't going to let her make the mistake of resigning as head of the Institute (as she was trying to do when he came into the room). He continued to be of great help to her in the following months and when she was made Consul, she put in the conditions that Will be made Head of the London Institute after her. She even stayed behind in London for the first few years before relocating to Idris to train and assist him in taking over.
- See more here
- Will was named after his grandfather, William Herondale.
- Will is the direct ancestor of Jace Herondale, one of the main characters of The Mortal Instruments.
- Like many of the Herondales that came after him, Will has an intense dislike of ducks. In fact, Will has somewhat of a phobia of ducks due to trauma from his childhood.
- Will has a tattoo of the dragon of Wales on his butt.
- Will and Tessa's wedding date is March 3, 1880.
- Will gave Tessa a number of meaningful wedding anniversary presents that Tessa still wears and carries even 75 years after his death. These gifts include the Wedded Union runed bracelet she wore for their wedding which he had made over with pearls for their thirtieth anniversary and a gold aletheia crystal he had Magnus enclose a happy memory into for their fiftieth.
- Because of how other Nephilim viewed and treated Tessa for her heritage, he and his family rarely spent time in Idris, except during the summers which they spent in Herondale manor.
- According to his children, if Will is singing, it means he is in a sociable mood and will seize them the moment he sees them to reminisce about Wales and ducks.
- While remodeling the Institute, during his period as the head, his wife found a cache of scandalous love letters between Charlotte Fairchild’s parents. No one besides him and Tessa has read them.
- Will has been going to a tailor named Lemuel Skyes for years. His son, James, thinks that he might be a werewolf.
- In early drafts, "Will was angry all the time" and had a different best friend instead of Jem, though the character was cut from the final version of the book.
- His fear of ducks was inspired by an experience that the author Cassandra Clare and her friend Sarah Rees Brennan had with ducks at Hyde Park.
- Will's unofficial death date is June 19, chosen by the fans for "Will Herondale Remembrance Day" and acknowledged by Cassandra Clare.
- The birthday (December 30, 1860) assigned to Will and revealed in the 10th Anniversary Edition of Clockwork Angel contradicts previously established canon: In Clockwork Prince, he said he was three months younger than Jem (whose birthday was revealed as November 8, 1860, making him only a month younger), and his birth year was listed as 1861 in the "found" family tree released with Clockwork Princess and An Illustrated History of Notable Shadowhunters & Denizens of Downworld, though the family tree may easily be considered inaccurate.
- Will and Tessa's wedding date was initially set to be March 9, 1879 according to a promotional, graphic art rendition of their wedding invitation posted by the author. It was changed before the release of the story the art was promoting.
- Clockwork Angel 10th Anniversary Edition
- "north. Near Dolgellau." Cassandra Clare on Twitter
- Clockwork Princess
- Character heights — Cassandra Clare on Twitter
- Clockwork Prince
- Clockwork Angel
- Nothing but Shadows
- Chain of Gold
- Chain of Iron
- Learn About Loss
- In Dreams Begin, a The Lost Book of the Whiteextra
- Wedding comic, a City of Heavenly Fire extra
- Fairy Tale of London
- The Lost Herondale
- Why Will Hates Ducks: A Clockwork Angel extra
- "Will’s dragon tattoo is in the 'buttchular area'" — Cassandra Clare on Tumblr
- Wedded Union rune tarot card
- Shadowhunter Army June 2021 newsletter
- "And Tessa and Will do not spend a lot of time in Idris..." Cassandra Clare on Tumblr
- Shadowhunter Army December 2020 newsletter
- Shadowhunter Army January 2021 newsletter
- "In early drafts, Will was angry all the time. He had a best friend. Not Jem." Cassandra Clare on Twitter
- "No, [the] character was completely cut." Cassandra Clare on Twitter
- "How did you decide that Will hated ducks?" Q&A — Cassandra Clare on Tumblr
- "In honor of Will Herondale Remembrance Day," Cassandra Clare on June 19, 2018 on Instagram
- "... it is the anniversary of the day he died…" Cassandra Clare on June 19, 2019 on Tumblr
- Preview snippet on Cassie's Tumblr
- "The correct date is March 3, 1880." Cassandra Clare on Tumblr