If your mother was awarded the house/property in the divorce, then it belonged to her. If she passed without a will, there is a statute that provides how her property would be distributed. Sec. 732.103 of the Florida Statutes provides:
732.103 Share of other heirs.
The part of the intestate estate not passing to the surviving spouse under s. 732.102, or the entire intestate estate if there is no surviving spouse, descends as follows:
(1) To the lineal descendants of the decedent.
(2) If there is no lineal descendant, to the decedent's father and mother equally, or to the survivor of them.
So, if your mom died without a will, all of the brothers (biological and legally adopted) inherited the property in equal shares. You did not have the legal right to sign a quit claim deed to her ex husband for the property after her death unless your brothers were in agreement.
The deed may be declared invalid. But because the transfer of property is SO VERY SPECIFIC, it is VERY important that you speak to an attorney who specializes in probate law. You may have not had the right to sign the quit claim deed. If that is so, and the deed is deemed invalid, then all of the brothers own equal shares of the property/house. If you can't agree as to how the property should be distributed or sold, you may buy out the interests of your brothers, or if there is no agreement among you, the property may even be partitioned by the court. Again, that is why you REALLY should speak to a probate lawyer.
I hope you find this information useful.
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