Hello Michelle, my name is***** am a practicing attorney in New York City. I am very sorry to hear that you and your son are being placed in this situation. You must be very upset and alarmed at this point.
The good news is that your son does have many resources available to help him with this situation - and so do you. Iowa has an excellent network of free legal aid resources where you can find lawyers who will represent you, your son, and your grandson, for free. I am posting a link to this resource here: http://www.iowalegalaid.org/
You may also find free legal help through the Iowa Bar Association: http://www.iowafindalawyer.com/iabar/AttorneyOnLine.nsf/Legal%20Assistance%20in%20Iowa?OpenPage
And through several law schools in Iowa:
Based on the facts you provided, both you and your son may have significant legal rights in this case. For instance, if your son's wife does get a divorce, he may be able to sue for custody rights after he is released from prison, and you might even be able to take custody of your granddaughter from his wife right now if your lawyer can convince the court that would be in the best interest of the child.
Your son's wife's threats about forcing your son to pay child support for another man's child are very unlikely to be successful. It is true that, under Iowa law, a woman's child is presumed to be the child of her husband. However, your son can easily prove that he is not the father of his wife's newest child by contacting Iowa's Child Support Recovery Unit within 20 days of receiving a notice of alleged paternity. The state will conduct a genetic test to clear the matter up. The test costs $600, but the state will pay the cost if the father is unable. You can learn more about this process (including the precise steps for contesting paternity) in this manual: http://www.iowalegalaid.org/files/A3ED30CF-AFFE-7431-9310-0D521E4312AF/attachments/99D68A79-1491-49B9-95EE-5941C28814D7/paternity-and-child-support-law-in-iowa-5-2011.pdf
That manual should tell you everything you need to know about paternity claims in Iowa. Nevertheless, you should contact the legal clinics I posted above immediately in order to get free representation for your son, for his child, and for yourself in order to secure all of your rights and make sure the child is given the best situation possible.
It is clear that you are a very responsible parent who wants the best for her children. I hope this answer has been helpful to you and that you speak with as many of the legal aid resources above as possible until you find a free lawyer that you are happy to have represent you. I am sure that you will find excellent care and valuable service if you reach out to these legal aid resources. I wish you, your son, and your grandson all the best with this.
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