When Lydia was about five or six months old, she was working really hard at crawling. Sometimes, she would push herself up on her hands, then slide uncontrollably backwards. Occasionally, she would push forward. Mostly, though, her arms collapsed under her during the operation and she'd bump back to the floor. Still, she would work at it for hours on end.
One day at the piano, I was watching her try to crawl along the hallway. The jerky up and down motion inspired this piece. After her workout, she was sitting on my lap and banged down her hands on the keys--what else would I expect. The cluster of notes became Lydia's Chord at the end of the piece.