<P> Jace, Clary, Alec, and Simon return to the Hall, only to discover that Sebastian has killed Max (Alec and Isabelle's younger brother). After Max's funeral, Jace sneaks into Clary's bedroom and tells her he loves her and always will . The two then fall asleep holding hands . The following morning, Jace leaves a note behind and sneaks off to find Sebastian . </P> <P> Clary manages to convince the Clave to fight together with the Downworlders and teaches them a binding rune so they can share their powers, which the dying angel showed her . While the Shadowhunters and Downworlders are forming their alliances with the rune, Alec kisses Magnus in front of the huge crowd, revealing his sexuality to his parents and the Clave . </P> <P> It is during this time that Clary discovers, after talking with her mother (who had finally awoken from the spell that Magnus used from the spell book) that she had received angel's blood while in the womb . She also learns that Jace is actually the son of Stephen Herondale, grandson of the last Inquisitor, and Jace had also received angel's blood while he was in his mother's womb . This means that Jace and Clary are not siblings and Jace does not have demon blood, but rather more angel's blood, and further reveals that Sebastian is actually the one with demon's blood and Clary's brother . </P> <P> Clary marks Simon with the Mark of Cain, a powerful protection spell, with the intent of saving him from Raphael, who says that vampires will only fight with Shadowhunters against Valentine if they give him Simon . The exchange causes the vampires to fight with the Clave . </P>

When does jace find out he's not clary's brother book
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