I never imagined a $12 prom dress would change three lives. I’d planned to skip prom—Mom couldn’t afford a dress, and I didn’t want her to feel guilty. But Grandma had other ideas. “Let’s go treasure hunting,” she said, leading me into Goodwill like it was a gold mine.

Most dresses were hopeless—until I found it. Midnight blue, floor-length, delicate lace. Perfect. Price tag: twelve dollars. At home, as Grandma tailored it with her usual magic, I found something near the zipper—hand-stitched fabric, and inside the lining, a hidden letter. It was addressed to a girl named Ellie: “I’m sorry I left you. I was 17 and scared. I never stopped thinking about you. If you want to find me, here’s my address. Love, Mom.” We were stunned. A dress carrying decades of regret and hope. The store couldn’t trace its origins, but I wore it anyway. That night, as prom queen was announced (me, shockingly), my literature teacher approached, wide-eyed.