You need to talk with a qualified family lawyer in order to have your question answered. And you need to do it in a confidential setting so that you can tell the lawyer everything the lawyer needs to know in order to advise your husband properly on what actions he can or should take.
The first -- and one of the most important issues in your case -- is what state would have the power to decide any change of residence issue. You indicate that your husband's divorce occurred in Kansas, but that neither he nor the child's mother nor the child now reside in Kansas. That probably means that Kansas does not have the power to make any modification to the existing child custody orders -- and that any modification must be made in the state in which the child now lives. This issue is governed by the Uniform Child Custody Jurisdiction and Enforcement Act (UCCEA). And so you should first contact a family lawyer in the place that the child now lives who has a good and detailed knowledge of the UCCJEA.
After you talk with a lawyer about which state has the power to make a child custody modification, your husband should then explore with the lawyer the specific facts he believes should lead to a modification -- and how he wants the orders modified. No matter what the situation, it is probably well worth making some changes to the existing child custody orders given as much time and changed circumstances as it seems have occurred since the original child custody order and the moves that both parents and child have made.
This response does not constitute legal advice and does not create an attorney-client relationship. I am licensed to practice only in Kansas. Seek legal advice from an attorney in your state or the state in which your legal claim exists.
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