What is the name of your state? MO
The state of MO allows a child support credit for children not part of the divorce/custody action who are in either of the parties custody, and that party is not recieving support for that child. The rules for this credit are: If one parent decides to have more children to get more/lessen child support, and that parent is the one who requested the child support modification, then those new subsequent children will not be taken into consideration in the modification calculation. However, if the parent who did not have the new children files for a modification, then those new children will be taken into consideration because their parent is not the one who asked for the modification.
Parent A has physical custody of the 2 children who are part of the divorce action. Parent A recieves child support from Parent B for those 2 children.
When the original order was made, Parent B had already started a new life and had a child who is still living with him. That child was taken into consideration in the child support calculation.
Parent A had an older child from a previous relationship who she left with her parents in another state. As soon as the current order was made, and after all these years (the child is 14-years-old,) Parent A pulled that child out of her parent's custody to finally live with her. We're thinking she did this because she found out about the credit given for this other child.
Parent A is fully aware of where this older child's father lives, yet refuses to file for child support for him. When the parents were together, Parent B urged her to file, yet she did not. So Parent B (when the child support order is eventually modified,) will have to pay a larger amount of child support when it is modified.
Is there any way to use that in court when the order is modified?
I understand it's Parent A's loss (of about $300/mo.) by not filing for support for her older child, but that is making Parent B suffer financially by paying for this extra child who is able to get support from other means. Yes, I understand Parent A is essentially paying for Parent B's new child (by getting less support via the credit given for him,) but Parent B is not getting support for this new child, and there is no outlet to get support for him. When the parents were together, this older child did not live with them because Parent A refused to take care of him (which enforces Parent B's hunch that she's just letting the child live with her for the extra money- she hasn't filed for a modification because she knows if she does it the child won't count.) Parent A has that outlet, yet refuses to use it... she's already told Parent B, "Why should I file for support for him when I can get it from you? Why deal with 2 people when I only have to deal with 1?"