My 18-month nephew has exposure to two pianos, one silent piano
at his grandpa's house and the other, a player, at my family home.
He likes to make noise by hitting the keys, as most kids do, but
until today had not seen the piano play by itself.
I put in "The Navajo Rag" and he jumped back with surprise and fear!
He didn't cry, but didn't feel comfortable being near the piano as it
played itself. Finally he got the idea it was okay and he started
Later we played the piano together, with him on my lap and his arms
holding on to mine, for the "Charleston". It sure is hard to play
stride bass with a baby on your lap.