Why do people have children?

There are many reasons people have children.  A common reason is simply tradition and expectations.  Some people have grown up expecting to have children, their parents expect them to have children, and all of their friends have children, so they have children.  Another reason is economic.  In agricultural societies children can be an economic benefit, providing labor to help the family manage the farm.  Another common reason is that children can provide support when the parents become elderly.  Finally, the parents may simply be looking for the meaning, affection, and love that children bring to their lives.