So like the title says, if the family is accepting food stamps, or any type of assistance from the government, they should only support up to two of the children so that way the parents aren't making more kids that are going to live in shitty conditions. They could still have them, but they would not get any help from the government. This also would save the government money as some women just have kids for the benefits. Families that have more than two children when they go into government assistance would be covered, and every one who is covered now would not loose their coverage. This would only apply if you had two kids and were about to have another while getting government benefits.
I believe that the U.S. Government should only provide assistance for up to two children if the family is under the poverty line to curb overpopulation, and poor living conditions.