Having children:

Costs: 

-paying for their education.

-providing clothing, food, housing etc.

-being responsible for someone else.

-spending time and effort on/with your children. 

-giving birth.

-worrying constantly about them.

Goals:

-to raise a morally good child.

-to teach them right from wrong.

-to teach them responsibility.

-to teach them to have a good work ethic so they can survive in the "real" world.