child support question for NJ any help will be appreciated.?

I have a friend named Heather that needs your help.We live here in SC but her new husband has a child in NJ.The mother has sent many emails and said on phone that the child is not his but he feels as though the child is.He does not in any way contest support payment.The problem is his payment is set at 1026.00 a month which is A LOT!! My question to you because Heather dont know what to do about this is ...is this a right amount.I mean he makes roughly 19,000 to 20000 a year.Can they get this recalculated.They just got married in april 2009 and they are too expecting a child of their own.I am writing for Heather.She is so stressed and has been through so much in her short beautiful life.(cancer,loss of family) Im worried about what the stress will do to her, the baby and their new family.She has the biggest heart and use to smile all the time now shes so stressed.Its hard to make this amount each month and live.How can they get it recalculated so that the amount is correct and can he ask to see the child.The child is 4 and he only seen it when it was small.He wants to do whats right and they have to be able to live too.Any help would be very appreciated.Thank you.They were never married him and his childs mother.He does want to help he just dont know how it got set so high and what he needs to do to lower it.