Childbirth is painful but necessary as well (labor pains), but forgotten quickly. Raising a child doesn't come with instructions, kinda have to learn as you go based on the fact that each child is different. The wisdom & experience comes along as you go, but there are others to help along the way if you're so lucky to have that help.
You're suppose to have more wisdom if you have a child when a bit older & more prepared, but not always the case.