The envelope jammed in Wren's mailbox wasn't hers. Same street, wrong number: 14 instead of 41, the digits swapped by some tired hand at the sorting office. It was addressed to a woman named Cordelia, in looping handwriting. Inside, a letter began, 'Darling, I know it's been too long, and I owe you the truth.' Wren stood on her steps, holding a stranger's letter, not sure what to do.

Wren grabbed a pen. Instead of delivering it, she wrote a note back: 'This came to the wrong house. I'm number 14, not 41. But your letter sounds important, so I'm passing it along.' She slid both into a fresh envelope and walked to the post box on the corner, dropping them in before she could change her mind.

The letter came back a week later, stamped 'RETURN TO SENDER.' Wren sighed. The address inside had been wrong too. But this time she noticed a phone number scribbled tiny on the flap. Heart pounding, she dialed it. A warm voice answered after two rings. 'Hello? Is this about Theo's letter?'