Well, its_me!, in another culture and another time....
In a modern industrialized, first-world culture, children are gifts. Expensive gifts; much helicoptered and fussed over. The love and funds that we lavish on them... I think the reason we can afford to do this is that every one of our children will likely survive to adulthood. To lose a child in our society is a huge tragedy. We have fewer of them because they are so darned expensive, but also because we are much more certain we get to keep them.
In an ancient, third-world nomadic household, children are assets. Have lots, because few will survive to adulthood. They are your guarantee of a peaceful and pampered old age. In context of when it was written, a fresh batch of children would be a symbol of refreshed prosperity.