Good morning. First, let me tell you how sorry I am for the loss of your dad. I know this must be a difficult time for you and please know I will keep you in my prayers!
As to your specific question, your step mother couldn't be more wrong. When there is no will, the Tennessee intestate succession laws apply and given there is a surviving spouse and you are the only child, your dad's probate estate would be divided 50/50. The specific statute is as follows:
Title 31 - Descent And Distribution
Chapter 2 - Intestate Succession
31-2-104 - Share of surviving spouse and heirs.
31-2-104. Share of surviving spouse and heirs.
(a) The intestate share of the surviving spouse is:
(1) If there is no surviving issue of the decedent, the entire intestate estate; or
(2) If there are surviving issue of the decedent, either one-third (1/3) or a child's share of the entire intestate estate, whichever is greater.
(b) The part of the intestate estate not passing to the surviving spouse under subsection (a) or the entire intestate estate if there is no surviving spouse, passes as follows:
(1) To the issue of the decedent; if they are all of the same degree of kinship to the decedent they take equally, but if of unequal degree, then those of more remote degree take by representation;
It's important to realize that certain assets pass outside probate and thus are not governed by the intestate succession laws. These include the following: i) joint brokerage and bank accounts which vest automatically in the surviving owner upon the death of one owner; ii) real property held as joint tenants or tenants by the entirety, which also vest automatically in the surviving owner upon the death of one owner; and iii) assets with designated beneficiaries other than the estate such as life insurance and retirement accounts.
With respect to the house, unless they own the house as joint tenants with right of survivorship, she's going to need your permission to sell the house, because you have a 50% ownership interest in your dad's share of the house.
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