Last night Chloë spent her first night sleeping on her tummy--by herself, that is. She's slept on me like that often enough. When I put her down for bed she grabbed her puppy and twisted onto her side, as usual, but after a minute she started crying, which was unusual. A little later music started. She's got a Fisher-Price aquarium strapped to the middle of one side of her crib, a hand-me-down from her cousin Gabriel, who loved it as a baby. It has swimming fish, a couple of levers to press to make a clam open and close or a starfish twirl (I think), and a big button to start and stop music and lights. I figured she'd kicked it with her foot, which has happened before, and the crying stopped shortly after, so all was well.
I went in later to check on her and found her on her tummy, scootched down in the crib so that her face was level with the aquarium, one arm outstretched. She had obviously flipped over, crept backward (because that's all she can do) until she reached the aquarium, and turned it on. She probably slept through the night like that, but she was practicing crawling when I woke up this morning so I don't know for sure.
She did the exact same thing tonight. I'm going to move that aquarium up tomorrow so she doesn't have to scoot so far.