You may have a good case here, but you need to find the right attorney, someone with many years experience in litigation. This is not just a probate question. DON'T WAIT. The applicable statute of limitations is probably already running, and you may be better off suing while he is still alive. Note that most attorneys will give you a free consultation as soon as you say the words "he promised me $5 million."
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.
I agree with Attorney Goodson. You may have a good case here, particularly because you have a signed letter and a copy of the will. There could be different court actions that are possible under the limited facts you have provided. As Attorney Goodson has stated, a civil action may not be limited to Probate. It does sound like you may have suffered legally enforceable damages as you relied on his promises of property and marriage.
One type of Probate action that is possible against the estate, after the death of the individual, would be under Probate Code Sec. 21700 (a), which states, in part, that a contract to make a will or devise (bequest) or other instrument, or not to revoke a will or devise or other instrument, or to die intestate can be established only by certain means including a provision in the will (subsection (1); a reference in the will or other written document to a contract or evidence proving terms of the contract (subsection (2)) or by a writing signed by the decedent that evidences the contract (subsection (3)).
It’s difficult to follow some of your facts here. You state that you are named as trustee but a will would nominate you as the executor while a trust would name you as trustee or successor trustee. Does this individual have a trust as well? It appears that this individual is still living. Did he change the terms of his will or trust after his agreement with you? Is he still legally competent? It is unclear how his secretary can claim everything if he is still living? Is he over age 65 and a possible victim of elder abuse? Do you believe that the secretary unduly influenced him?
If you would like to provide additional facts in the “comment” section, I’ll try to answer your questions more completely. Also, I am located in San Diego, so you can contact me directly as well.
Disclaimer: The above answer does not create an attorney/client relationship. My responses are intended to provide general information about the question posted. I am licensed to practice in the state of California. The information provided on this site should not be used as a substitute for conferring with or hiring a competent legal advice from a licensed attorney that practices in the subject area in your state.
Attorney Rosemary above may be a good resource for you as she identified the key issues. The strength of your case improves if you fully performed your obligation to care for him. In other words, your case is stronger if you cared for him up to the date of death or until he was placed in a care facility. You have then fully performed your obligation for care. The letter may contain sufficient language to be a contract. Even if not enough to constitute a contract, then that may still be fulfilled as your services for many years were performed on reliance upon that written promise. There are specific statutes to consider regarding a caretaker inheriting. However, those may not apply of the agreement was made prior to you providing services as a caretaker.