How do you know when to stop paying child support when the court order doesn't have an ending date for child support to stop?

Usually reasons for child support to end are because the child graduated from high school, oe the child has married. If the order does not designate a specific date for the support to end, the termination date would be when the child reaches the legal age of majority of the state in which they reside. Please be advised, in most states a motion must be filed with the court to cease support on the grounds that the minor child has now reached the state's legal age for being an adult.