If probate was never opened, the issue is who was awarded the house in the will? Also what was the value of the property at the time of death? Depending on these answers your mother may have to open probate or you may be able to transfer the property by affidavit. You definitely want to consult with a probate attorney.
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Pretty obvious-you need to hire a probate attorney to check the court probate records and advise you further.
The answer given does not imply that an attorney-client relationship has been established and your best course of action is to have legal representation in this matter.