According to this source:
http://family.findlaw.com/child-support/when-does-child-support-end-.html
“In most states, child support ends when a child turns 18 or graduates from high school, whichever occurs FIRST. In other states, the age may be 21.” With these possible exceptions: “In most states, child support ends when the child reaches age 18. Some states, however, allow child support to continue beyond 18 in certain circumstances, such as if the child is still living at home and attending high school, or if the child has special needs.”
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