Children are not a zoo of entertainingly exotic creatures, but an array of mirrors in which the human predicament leaps out at us.
Having children is something we think we ought to do because our parents did it, but when it is over the children are just other members of the human race, rather disappointingly.
The fullness ends when we give Nature her ransom, when we make children for her. Then she is through with us, and we become, first inside, and then outside, junk. Flower stalks.