Toothbrush trouble

Scene 1: Michael enters bathroom and screams in horror as he sees Zane, completely naked, grinning hugely as he waves Michael's toothbrush over the open toilet. Apparently the electric toothbrush is dancing. There is no clear evidence of contamination, but the circumstances were such as to necessitate a full sanitization of all objects and children involved.

Scene 2: Two days later, Zane walks into my bedroom, singing a happy tune.  I look up to see he is (again) completely naked and cheerfully singing "I clean my bum, my bum so clean!"  I realize he is scrubbing his cute little bum with his big brother's electric toothbrush. There are some sort of bubbles involved. Toothbrush is promptly confiscated before persnickety Jed realizes the nightmarish nature of the infraction.