It is imparative that children learn this trait early. I think it's very important to give your children as much respect as you would like them to give you in return.
Children parrot what they learn.
And it is so nonproductive. As parents, we are our children's role models. My children are learning to do the same. Confidence comes from the positive feedback from the parents beginning from the moment they are held in mommy and daddy's arms. Take it from someone who knows.