Two weeks ago, as my mother in law was dying, she gifted my wife a lockbox filled with cash and savings bonds. The cash is over $10k but I don't know the full amount. It had been stored in the lockbox because of marital problems my in-laws had- Notes indicate my mother in law may have been saving it to use for a divorce lawyer. None of which is really important anymore given her passing.
I have an active TS clearance as a contractor. I am planning to document the full amount of this money and self-report it. How do I go about it? Do I call my corporate security officer or a central number? Is there a form? Do I need to get an official copy of my mother in law's death certificate? I do not want there to be any concern that my wife might open a new bank account with a large amount of cash and want to follow all regulations.