First of all, because there was no divorce, your stepmother remained your father's legal spouse. Secondly, you did not mention a Will assume that your father did not have one.Accordingly, his estate will pass via the "intestacy" laws ofthe state in which he was domiciled as of the date of his death. Typically, a surviving spouse is entitled to 1/2 -1/3 of the assets and the deceased's biological/adopted children inherit the remainder (however, this varies from jurisdiction to jurisdiction).Note: As to the real estate, it will pass by intestate succession since her name was not on the deed (the names on the mortgage have no legal bearing).