You are going to need a lawyer, or lawyers, to sort out who owned what when, and how much of the property was a gift versus an inheritance. There might also be a question about whether your mother-in-law retained a life estate when she put your names on the deed. A life estate could be specified in the deed, or it could be implied or de facto. The lawyer(s) will have to examine the exact wording of the deed and any other related documents, as well as your mother-in-law's will and any probate documents. There are issues involving real estate, wills and estates, and income tax, so you might need more than one lawyer, or a law firm that has lawyers with expertise in all three areas. If you know the lawyer who prepared the modified deed, that might be a good place to start.
