She stumbled backward onto the porch. The front door slammed itself and the deadbolt clicked five times, slow and deliberate. Through the frosted glass she saw Katie shrug, laugh, and turn away, already forgetting Sarah existed. Balloons inside the foyer multiplied, filling the air like red blood cells. Sarah ran to her car, but the key wouldn’t turn. The dashboard lit up with a new GPS destination: 3:33 p.m. tomorrow, same address, labeled “Housewarming — Bring yourself.” The radio crackled on, playing the birthday song in a child’s voice that sounded exactly like her own at age seven. Every station, same song. She punched the radio silent. In the cracked rear-view mirror, the house waved goodbye with a curtain.