Twenty years after her little sister Anna vanished during a school camping trip, Claire is a married mom still haunted by the loss. She’s extremely protective of her son Ethan, terrified of history repeating itself. One evening, after meeting her friendly new neighbor Rachel, Claire spots something in the garden: a tiny wooden heart keychain with a silver key — the one she carved for Anna as a child. It had disappeared with her sister the night she was lost near a rising river.
Shaken and sleepless, Claire shows the keychain to her husband, convinced it’s Anna’s. Suspecting Rachel, she visits her and learns they were actually childhood classmates, not sisters; Rachel has no shoulder birthmark like Anna’s. Embarrassed and exhausted, Claire starts to doubt herself and considers that maybe Ethan found the keys in an old box by accident. She heads home, trying to let the obsession go.
When she returns, their nanny Lily is playing with Ethan on the floor. Lily happily says she’s glad Claire “found my keys” and holds up the wooden heart and silver key. Stunned, Claire asks where they came from. Lily explains she’s had them since she was a child, found with her when she was discovered by a riverbank and adopted — she has no memory of her life before that.
Heart pounding, Claire asks Lily to show her shoulder and sees the familiar birthmark Anna had. She pulls out an old photo of two girls in matching dresses, one holding the same keychain. Lily breaks down as the truth hits: she is Anna. Claire embraces her, whispering, “You’re home now.” After two decades of grief and uncertainty, the missing piece of Claire’s family has finally returned.
