The master RBF first flew when he was two. The car seat secured him well enough, but I noticed on taxi that he would reach out to the yoke which was all the way back at the time. He was told not to touch without asking first and that worked out fine. He also had ear muffs.
His difficulty was crosswind landings when he could get sick in the flare -- that's not a time when you have enough hands; so, bring the normal small children items for cleanup and extra clothes
Somewhat later he took fright when approaching overwater. Your own children will have their own particularities and there will be times flying the a/c takes priority over placating the little ones
