The fact that Stella points at one of the twins in the pictures and claims that it’s not her is a dead giveaway to Kennedy that her mother is lying—after all, how does Stella know which twin to point at, if it isn’t her? Kennedy herself certainly can’t tell the difference, so her mother’s ability to zero in on a specific twin reveals her lie. Still, Stella remains unwilling to tell the truth, since she has sacrificed so much to put her past behind her.