I'll take a guess and try to further define your custody order:
Unless otherwise noted within the four corners of your custody order, the child's mother and father will alternate weekly caring for their child(ren) and adhering to the traditionally accepted and observed holidays.
If you are unclear on any aspect of your custody order, always seek clarification from your attorney.
If you don't have an attorney (or didn't have one during the divorce or custody proceeding, take your documents to a local family law attorney and seek clarification.