First, a little background. Please forgive the rather dry read: When someone passes away, then their estate has to be distributed. The problem is that without probate - with assets such as titled property or bank accounts (those that do not have a pay on death clause) - this is hard to do. This is because you cannot switch over the assets without an order from the probate court, and simply a Certificate of Death will not do. A Certificate of Death simply states that someone has passed on, but does not give you the right to really do anything in the deceased's name. Also, non-titled items can also fall under this as well!
So one files probate. Once probate is filed, the Executor of the estate gets something called a Letter of Testament/Administration (hereinafter "Letter"). This Letter will allow the Executor to switch over the assets from the deceased individual to whoever will own the property. It is like a "Power of Attorney," but from the Court. Without that Letter, there is no way to transfer titled property and switch the assets into the heirs' names.
If there was a Will, the beneficiaries are decided per the Will. If there was no will, the beneficiaries are decided by default succession law of the state. You can see the default succession law HERE - scroll down to Who Gets What.
Now let's apply that to the matter at hand. You do not know if there was a Will or not. Assuming that there was not, then his surviving spouse inherits the first $75,000 of his intestate property, plus half of the balance, and the children (i.e. you) inherit everything else. If there WAS a Will, it overrides that. There is no right to a certain guarantee for children under the Will - he could have written you out.
The problem is that no probate was filed - it seems. A Utah probate must be filed within three years of the decedent's death. Utah Code section 75-3-10. It has been more than 3 years. Probate may still be filed for the purpose of establishing heirs, but if there was a Will, it can no longer be probated. Someone in your situation may wish to talk to an attorney locally to see what options there are to possibly probate the estate either way, if possible, to get whatever one would get under the default succession laws. Any interested party can initiate probate.
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