Are you the person who taught him Offenbach's "Galop infernal"?

Well, I've certainly played it for him, maybe half-a-dozen times at long intervals over the last year, so he has a fine musical memory. I tend to break it out when he's in that state of joyous rampage, most vividly once in the bathtub, while he can-canned his bubbles into meringue.

Nine