Distance will be key, an initial assault on you while your either carrying your child or holding his/her hand is a tremendous threat.
One that even in a non CCW state could be considered a lethal threat easily. Those LEO batons, stun gun, not really in favor of pepper spray while holding a child. wind, fighting etc,...
Hand to hand, all bets are off, kick to the groin, gouging of eyes, etc,... if the assault doesn't stop, your in for the fight of your life and your child's life.
Pocket knife, lethal force of any kind, will have to be considered. Your child will survive being "dropped" so you can defend yourself and your family.
As a father, that would be one of the worst attacks I can imagine. I would run for distance, and if not possible, I would literally go to rage mode, child down, retaliation of a swift and blinding nature with anything at my disposal.