Having a child is like causing your own immortality. Your genes live on in your child, and your ego really wants that child to be the best… better than you.
You want to live through your child, and you want it to be glorious, even if your actual life is… hm… shitty?
The child, by the way, considers this an unfair binding… and resents it, wiggles out of it… the child wants to be free, make her own mistakes… have a life that is hers alone.
That is the norm.