If that's required in your state, both parents.
no
it goes directly to the child.
His parents pay for him and he pays child support for his baby.
The parent that pays child support does not need to pay child support for her child`s kids, only the current right parent.
In short, no one.
Child support is court ordered. The judge decides who pays child support and how much.
Depends on the state.
Social security
yes
Yes, if she has an older child she currently pays child support for.
Social Security pays for the child until he or she is 18 years of age.
Child support is for food, housing, shelter and anything else the custodial parent decides is necessary to support the child. The courts frown upon non-custodial parents not contributing to extra-curricular activities, school supplies and medical co-pays.