I do not practice in PA, so I am not sure of the answer to your question. IT is one of my favorite states however! In Massachusetts, this would not normally be allowed by the courts once a divorce has been filed, but you have not filed yet. Although you should meet with a lawyer, you could also consider calling the insurer directly and see what is required to be reinstated on the policy. I would also contact the state office that handles insurance and ask them what the rules are in PA for your situation.
As a related matter, you should consider moving forward with your divorce. For one thing, it will help tie up any loose ends, and then you would have a divorce agreement setting forth the terms - including health insurance coverage and child support issues.
Good luck with your case.
If you have a divorce filed, you need to petition for special relief to make him add you. He is supposed to maintain the status quo on insurance until a decree is entered and you can sue him for any out of pocket medical bills you incur for him dropping you as long as you take action. If your son is a minor he can be obligated through child support to carry him so make sure you have filed for child support as well.
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