In my county, our child support is handled throught the Department of Child Support Services. I don't know if that's how it is where you are.
We have an order. While an order is in place, that is the amount due. If it's not paid, then the unpaid amount becomes arrears and the arrears accrue interest.
If your ex wants to lower his support amount, he can always petition for a review and request the amount to be lowered. (Through the county support division, that doesn't cost anything).
However, at least in the instances I am aware of, it doesn't matter if a man goes on to have 2,3,4, or 5 more children. He is still responsible for the first child. And, if he can't afford to support the first child, he has no business having subsequent kids to care for.
Also, from what I have seen to be true.....they don't lower support if a man chooses not to work, ESPECIALLY if he chooses not to work so he can stay home and take care of a subsequent child from another relationship while the mother of said child works to support him.
If she wants to support him, that's her business, but your ex still has a responsibility to your child.
If you don't have your support case handled through the local D.A.'s Support Division, I strongly advise having them handle your case. It doesn't cost anything. Not only that, even if he doesn't have a "job" that they can garnish his wages, they can take any tax returns he is entitled to.
I'm not sure how it works, but I would assume that earnings from sales on e-Bay are reported as income.
They also take into consideration his earning potential.
My ex deliberately quit a $150,000+ a year job because he refused to pay me support based on that amount.
The court was not amused.
My point is, you do not have to agree to lowering support for your child just because he has another woman pregnant and is choosing not to work.
You don't have to agree to anything at this point. Every month he doesn't pay the full amount just adds to the arrears and every month, that amount adds interest.
What he and his fiance decide is reasonable is moot. They are going to base that amount on THEIR needs.
The court ordered an amount based on your child's needs and if I were you, I wouldn't agree to anything. If he wants it lowered, make him go through the channels to have it reviewed either by the court or the child support division.
I'm all for compromise, etc, but in this case, I wouldn't sacrifice anything for the convenience of his new life.
Just my opinion.