I am an attorney practicing in Colorado and New York. I can give you some general advice on this topic, but you will need to confirm the information with a local attorney. First it is important to know if your father had any assets that were not owned joiontly with his wife. All joint assets would pass to her regardless of the Will. Assuming he had assets soley in his name, and assuming your father had a Will, the Will would need to be Probated to have the named Executor appointed and his assets distributed to the named distributees or beneficiaries. In order for the Will to be admitted to Probate a Petition would need to be filed in the Surrogate's Court in the County where your father lived at the time of his death, and the Petitioner would need to serve all his children with a copy of the Petition along with a copy of the Will. You would have the right to challange the Will or seek some further relief at that point. Sentimental items are usually something handled outside of the Court and resloved through the attorney for the Estate.
As a practical manner, you really should try to speak with your moth-in-law to see if there was a Will and/or if she will be bringing an Estate proceding to have it admitted to Probate. If all assets were jointly held she will likely not even do so.
I hope this answers your question, and puts you on the right track.
If your father left a will - a probate proceeding will need to be opened to transfer certain assets under the will. The will will then be filed with the court and will become public record. If your father died without a will (intestate), the same process will have to occur. Under intestate succession, you and your sister are heirs. If your father left a living trust, under California state law, you will also be informed when the administration of the trust is opened and you are entitled to a copy of the trust.
If you're simply not getting answers from your stepmother, or if you are suspicious of her answers, you can take action in your own right. If your stepmother is not opening a probate case, then you can do it as prospective heirs. Then if there is a will, your stepmother will submit it to probate and you'll be entitled to a copy, and if there is no will then you may be entitled to a share of the estate under the intestacy laws. Good luck.
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