I have a colleague in the Fresno, CA area who might be of help to you. Here is his contact information: Attorney Robert Wright of Wright & Wright Attorneys at Law, Inc. (265 E. River Park Cirle, Suite 260 - Fresno, Ca 93720) 559-228-8184. You can also email him at firstname.lastname@example.org. He is also a fellow member of wealth counsel, link provided below. Good luck to you!
You are on the right track. You DO need a probate attorney. You have already waited on this, longer than you should have. No one on Avvo can tell you the answer to your situation, because it depends on the documents in question. Whether or not you can do anything about this depends on how it was done. Proving that the documents were fraudulent may be next to impossible. Doing so would almost certainly be exceedingly expensive, and it would affect your relationship with your family.
If you can PROVE that the documents were "falsified," then you may want to darn the torpedoes and full speed ahead. Otherwise, depending on what you are after, you might consider a different approach. If you have contact with your brothers you might ask them if there are things of your parents that you can have. If they shoot you down, then you can always consult with an attorney. These kinds of cases are lengthy and expensive, in most situations. You will also want to ask the attorney about the statute of limitations. It may have run on this.
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You have already waited too long to proceed on this. Do not wait any longer. You need to consult with a probate attorney in the area where the estate was probated. Be sure to go over all of the information you have with the attorney, and you will need an in depth analysis based on your particular facts.
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