Yellowfang is an old dark gray she-cat with a broad, flattened face
Yellowkit is born to Brightflower and Brackenfoot of ShadowClan, along with her siblings Nutkit and Rowankit. Yellowkit notices that her stomach aches, and her sibling, Nutkit, does too. Nutkit ate a tainted piece of crow-food, and Sagewhisker gives the kits yarrow to induce vomiting. Yellowkit insists that she didn't eat the crowfood, and she's hurt when her mother thinks she is a liar.She notices that Silverflame is becoming finicky about food and hasn't eaten much. She tries to get her grandmother to eat a frog but the elder hardly takes a bite. Yellowkit starts to feel the sickness that Silverflame feels.Several moons later, Yellowkit, along with her siblings, become apprentices. Yellowpaw gets Deerleap for a mentor, and she's satisfied with that. When Yellowpaw and Deerleap are about to go explore the territory, Yellowpaw feels pain in her chest. Yellowpaw dismisses her aches and views the territory with her new mentor, but worries about Silverflame. When she comes back, her mother tells her that Silverflame is dying. Yellowpaw cannot believe this and goes in to say goodbye to her grandmother. She is grief-stricken and angry at Sagewhisker, thinking that she could have done something to save Silverflame.Some time later, Yellowpaw earns her warrior name, Yellowfang. She becomes very close to Raggedpelt, wanting to be with him forever. Sagewhisker talks to Yellowfang about her ability to feel other cats' pains and says she should be a medicine cat, but Yellowfang disagrees. Over time, Yellowfang realizes that she can't focus in battle when she feels her own pain plus everyone else's. She later reluctantly decides to become Sagewhisker's apprentice and train to become a medicine cat.Later, Yellowfang tells Raggedpelt that instead of being his deputy, she'll be his medicine cat, but they both want more than that. They agree to meet in secret in parts of the territory, which Yellowfang knows is breaking the medicine cat code. When she goes from apprentice to full medicine cat, they are forced to stop being together, much to Raggedpelt's frustration.At a Gathering, while Yellowfang is sitting with the other medicine cats, she feels a strange movement in her belly and wonders which of the queens is expecting kits. With horror, she realizes that the feeling is her own and she is the one carrying kits. She scuffles around uncomfortably in the leaves until Sagewhisker asks her if she'd eaten a piece of crow-food.She continues her medicine cat duties, but on a walk one morning, Sagewhisker eventually uncovers her secret. The medicine cat lets her apprentice keep her status, but confesses that she is a little mad. Sagewhisker reminds Yellowfang they had taken vows and that the Clan needed her.Yellowfang sneaks out one night, feeling that the kits are coming. She finds a hollow log and tries to settle down. The birth is painful and she gives birth to two she-cats and a tom. One of the she-kits is stillborn while the other is very weak. Yellowfang desperately tries to keep her alive, but the other she-kit dies as well. In the end, only the brown tabby tom is left. She carries him home, where Raggedstar fusses over him and calls him his son. Lizardstripe, a queen at the time, nurses him reluctantly. Yellowfang says that his name is Brokenkit. Lizardstripe thinks he was named for the broken tail, but Yellowfang reveals in the narration that it is really because of Yellowfang's broken heart. Sagewhisker then gives Yellowfang parsley to stop her milk. Yellowfang says to StarClan that Brokenkit is no longer her son.