In season 3, Peyton learns that she was adopted, and that Ellie really is her biological mother. Lucas witnesses Ellie purchasing drugs, but he learns that she was buying them for medical reasons; she has breast cancer. Meanwhile, Peyton is angry with Haley because she left Tree Hill to go on tour, but soon they make amends, and Peyton reveals that her hostility toward Haley was because she was the only one that came back out of all the people who have left her. Peyton soon grows close to Ellie, and they collaborate on a CD called Friends with Benefit, which benefits breast cancer research; there will also be a concert for it at TRIC and Haley is one of the performers. Unfortunately, Ellie dies before she sees the CD or the concert, leaving Peyton devastated. A school shooting breaks out later in the season ("With Tired Eyes, Tired Minds, Tired Souls, We Slept ''), where Peyton is left fighting for her life after being the one shot. Lucas and Nathan run inside the building to save Peyton and Haley; Lucas finds Peyton bleeding out of her leg inside the school 's library. She can not walk due to the injury, so escaping is out of the question. Lucas and Peyton stay in hiding, and Lucas wraps her leg, hoping to help the bleeding and pain subside. As Peyton is falling in and out of consciousness, he forces her to talk about a fun day she once had. Minutes later, after earning a promise from Lucas about everything being okay, Peyton loses hope of surviving, despite Lucas promising to get her out of there alive; she kisses him, wanting to let him know that she loves him before she dies. Lucas returns the kiss, and Peyton soon falls unconscious. Lucas, not wanting her to die, carries her out of the building, even at the risk of being killed by the shooter.
when does peyton find out she's adopted
In season 3