Your influence as a role model is essential here. Supervise any interaction between your child and the cat until you are confident both are behaving properly. Bring the animal to the child and help your youngster pet him, stroking with the fur, not against it. Teach your child how to hold the cat so that he is properly supported. And more importantly, your child should know when to let the cat go.
Kittens are delicate and can be injured by a child's overly tight hug.
And don't allow a child to tease the cat, or to disturb him when he is eating, using the litter box or in a deep sleep.