In Texas, one parent pays child support to the other. It is based solely on the payor's income and is a straight percentage 25% for two chilren. The income of the parent receiving child support is of absolutely no consequence to the amount of child support paid.
http://tlo2.tlc.state.tx.us/statutes/docs/FA/content/htm/fa.005.00.000154.00.htm
http://tlo2.tlc.state.tx.us/statutes/docs/FA/content/htm/fa.005.00.000154.00.htm