The envelope showed up on a Tuesday, sea-blue and soft at the corners. The handwriting belonged to Theo, Mara's best friend from when she was eleven. Twenty years of silence, and now one line inside: "I found the map of Saltreach in my mom's attic. The lighthouse is still unfinished. Want to build it?" Mara sat down hard and read it three more times.

Mara grabbed her phone before she could talk herself out of it. The number on the back rang twice. "You actually called," Theo said, like he'd been holding his breath for days. "Saturday. Meet me at the old dock. Bring boots." Mara laughed for the first time in weeks and said yes.

When Mara reached the dock, Theo wasn't alone. A girl about nine stood beside him, arms crossed, studying Mara hard. "This is Birdie," Theo said. "My daughter. She's the reason I finally opened that attic." Birdie held up a folded paper boat. "Dad says you two were going to build a real lighthouse. Were you lying?"

Birdie's question hit harder than Mara expected. "No," she said quietly. "We meant it. I'm the one who never came back." Theo looked away. Mara realized the build wasn't only about stone and timber. It was about whether two grown-up kids could forgive themselves. "Let's start tomorrow," she said. "All three of us."