Lost Will Found

I think that you have written two questions here so I will try and answer best for both.

It is my understanding that there are no time limits in California to probate a Will.  As long as the Will can be authenticated by the subscribing witnesses then it is valid.  If it has affidavits attached already then you are in even better shape.

It sounds like a lot of things went on in your family from the time your Father died until now.  If your Father was thought to have died intestate (without a Will) the intestacy statutes would have kicked in and you would have indeed gotten a share of his estate. If your Mother (his wife) was alive as well then I am perplexed as to why your brother ended up with everything.  Were there other documents as to the companies that may have been in effect such as partnership agreements?

The Will probably names an Executor or Personal Representative as it is called in some states.  That person should take the Will to a Lawyer to being the Probate process.  Please note that although a lawyer is not always needed for probate the circumstances as you have written I think may require good legal counsel in your area.  Once a personal representative is appointed that person(s) have great power given them under the law to do what is necessary to "right" what you believe was "wronged".  How it is approached under the circumstances can not be determined in this forum.  Good luck.