My condolences to you and your siblings on your mom's passing.
Those assets belonging to your mom may automatically pass to beneficiaries under designations in account documents, such as joint tenant with right of survivorship, payable on death, transfer on death or ordinary beneficiary designation such as a life insurance policy or IRA.
Those assets that do not automatically pass to anyone will be governed by the law of the state in which she resided. The assets may need to go through probate, which is the process of determining who are the deceased's statutory beneficiaries and changing title from a deceased owner to her beneficiaries.
Some states allow a process of resolving estate distributions using family settlement agreements.
To expand on Mr. Greening's answer, any assets not covered by a contract (e.g., life insurance, pay-on-death accounts, joint tenancy) will eventually be distributed to what are called the "intestate heirs." Your mother died "intestate," which means without a will. As such, the state where she was living has rules, typically in the state's Probate Code, which govern the distribution of intestate assets. The most common distribution given the facts you present is equally between the children. However, there can be caveats. In California, for example, the children of a deceased spouse might be entitled to inherit a portion of your mother's estate that came to her through her marriage to the spouse.
Furthermore, it might be necessary to go through the probate process before distribution. Without more facts, it's impossible to say. Therefore, it's very important that you consult with a probate attorney versed in the law of the state your mother was living in at the time of her death.
I am sorry about your mother's death. As the other 2 lawyers explained, if there are beneficiary designations on her assets (such as bank accounts, life insurance policies, IRAs, etc.), those assets will go to the named beneficiary. Her other assets will be split between her "heirs" according to the laws of intestacy in the state where she lived. However, the assets may be subject to creditors' claims that have higher priority than the "heirs" - that is, if your mother owed anyone money (credit card debt, IRS taxes, etc.), those creditors usually have the right to be paid first, and then the heirs receive what's left over after all of the debts have been paid.
The information you obtain at this site is not, nor is it intended to be, legal advice. You should consult an attorney for individual advice regarding your own situation.
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