S.G.
Well, I started my daughter around 13/14 months brushing her teeth. I began with giving her the brush to chew/play with in the tub. After 1 or 2x, she lets me brush her teeth no problem every night before bed ( we only use water for now, as I think paste is a bit much for her young age)I brush her teeth 1st then let her play wit hthe brush after I'm done. I'd try to let him play with it on his own, so he won't be so hesitate when the time comes to brush.