Are Jim Bob and Michelle selfish for having so many children, when overpopulation could be a problem?

There's no way that they can give each and every kid their undivided attention in a 24-hour period, not even for an hour a day.

I don't know if it's true but from what I've read, the kids have a sign up sheet on which they must put their names in order to get one-on-one time with their parents.

The older kids supposedly have a so-called "buddy system" and have to help care for their younger brothers and sisters.

The Duggars seem like a nice and well-mannered group, at least from what I've seen and they can [again, supposedly] afford to take care of such a large family unit.

However, what kind of impact are the Duggars creating on Earth and its limited resources by having so many offspring?