Must the noncustodial parent pay support if the child is with him or her for summer vacation?

Courts reason that many major expenses for the benefit of the child—such as rent, mortgage, utilities, clothes, and insurance—have to be paid whether the child is with the custodial parent or not. So, usually, a full support payment is due, even if the child is with the noncustodial parent.

On the other hand, the parents themselves are free to set payments in different amounts during vacation periods when the child is with the noncustodial parent. The lower amount for vacation periods with the noncustodial parent might reflect savings to the custodial parent for food expenses or child care.

Read more at:http://www.americanbar.org/groups/public_education/resources/law_issues_for_consumers/childsupport_summervacation.html