How do they manage?

Certainly love plays a large part in it.

But the Duggars' parenting methods are inspired by a controversial religious curriculum called Advanced Training Institute.

The Duggar family in 2014

“The emphasis is on training a child before the need to discipline arises,” they write.

Eventually, the child learns to stay put.

Critics argue that the cost of obedience isn’t worth it.

Baby on blanket with toy

The American Psychological Association has issued aposition paper on physical discipline.

Studies also show that corporal punishment really doesn’t affect the likelihood a child will stop a negative behavior.

Other portions of the Pearls' book are just as concerning: Is your child late to potty-train?

Wash them with a garden hose if they poop in their pants.

Do you give your baby bottles or pacifiers?

You’re setting them up for obesity.

And don’t forget to teach your girls how to keep house and your boys how to be manly.