Alissa, apparently remembering a story I'd told her recently about how she locked me out of the house when she was 15 months, decided to play a trick on me. She didn't just decide to lock me out, though, she really put some thought into it. When I came back to the door after my task, I found the door closed and deadbolted, but sitting on the railing next to the door were my keys.
I unlocked the door and congratulated her on her trick. She's very proud of her April Fool's.