If you have counsel, you should direct this question to them. You cannot normally compel a co-tenant in common to sell their interest, except in a Circuit Court action for Partition. This would follow the Estate transfer of the interest to you and your brother. And unless the mortgage is paid, you and your brother will take subject to the existing lien. Also, is there a divorce decree that incorporates an agreement about disposition of the house? Is she living there? Does she have a right to proceeds? So many questions for your lawyer to sort. So, before you engage in all this stuff, seek advice on the ultimate goal, and how it may be achieved.
You need to speak with a local probate attorney.
Your post does not indicate whether your father had a will and if so that it specifically devised his interest in the home to you and your brother.
The probate court likely has no authority to sell the home since you only own, at best, a 1/2 interest.
You will need to file a partition action.
I am not a MD attorney, laws vary from state to state, therefore you should always consult a local attorney.
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