Can I just add (although it might not be relevant to your situation) that sometimes even the primary carer who has significant care has to pay the non custodial parent child support. This happened to me, as well as my former boss.

I ended up dropping a day of work to avoid it. My ex has my DD about 70 nights a year and in 8 years has paid a total of $668 child support. There was no way in hell I was giving him a cent!!!