Ok. An action for retroactive child support is possible. Take a look at the law:
I know it isn't clear with all that legal mumbo jumbo, so I will try to break it down for you. What you want to look at is here:
Rule 1910.17. Support Order. Effective Date. Change of Circumstances. Copies of Order. Priority of Distribution of Payments.
(a) An order of support shall be effective from the date of the filing of the complaint or petition for modification unless the order specifies otherwise. In a child support case, if a change in custody occurs after the date of filing, but before a domestic relations conference is held, the trier of fact shall enter a charging order going forward in favor of the primary custodian that shall be effective from the date of the change in custody. The trier of fact also may enter a retroactive arrears order in favor of the party who was the primary custodian at the time of filing. Such an order may address the period from the date of fining to the date of the change in custody. However, a modification of an existing support order may be retroactive to a date preceding the date of filing if the petitioner was precluded from filing a petition for modification by reason of a significant physical or mental disability, misrepresentation of another party or other compelling reason and if the petitioner, when no longer precluded, promptly filed a petition.
So there may be a problem there in that you should have filed this action a long time ago and the court will want to know why you didn't. I don't really need to know the reason, but you should probably hire a good family law attorney to represent you in court in Pennsylvania in order to try to get this to work. So there is a possibility of getting retroactive child support for both of your children, but it isn't guaranteed.
Here are a couple of cases that you can read as well:
Because this will not be easy to do, you should hire an attorney in Pennsylvania to represent you in this matter. You can look for one at www.avvo.com or www.lawyers.com.
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