So much depends on the particular facts of the case. If he has property or kids or a disagreeable wife, perhaps he should wait to make parole. He may need to appear before a judge to get what he wants. Being in the joint, he can't do that. You would have a difficult time doing it for him.
I am not intending this to be legal advice, because I don't know the particulars of your situation. Call me if you would like to discuss this or other isues.
Yes he can get a divorce in prison. I have handled a divorce recently for an inmate however, as the initial contributor stated, if there is property or children involved, he may want to wait. His ability to make appearances and prepare for any contested hearing is severely hampered. If it is just an agreed divorce, or no property of consequence and/or children to be dealt with, you can have his wife file the divorce and get a waiver to your brother to execute so she can handle it. Even if your brother files it from prison, his wife will have to attend the prove up hearing at the end, meaning that her cooperation is going to be necessary to some extent no matter what.
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