When a woman gives birth to a child, the child needs to be able to digest the mother's milk; but when this child is old enough to begin to eat other foods, there is some switching off of this ability to consume milk.
I can't frankly see much difference in the film industry at all. The only difference might be that they don't take as much time as they used to. For example, they'll do in one day what we used to take a week to do.

