Hi, Tim!
If your lands are in Texas and the County’s Records are available online, I will be happy to scratch up what I can about the history of the land. To some degree I can also help if they are in Oklahoma.
But, honestly, I have to agree with Nancy and John: If everyone has stopped speaking to you about all of this, then it’s time to Lawyer Up.
It seems to me that if your Mother is the Trustee of a Trust, any leases she would sign as Trustee the company’s Attorney would make it a Requirement that the Beneficiaries of the Trust Ratify the Lease. And yet, no one is sharing any information with you.
Who else besides you and your Sister could possibly be a Beneficiary to the Trust?
How was the Trust Set up? Under either your Grandfather’s or Father’s Will or a stand alone Trust established when they were alive?
What is the name of the Trust in the papers the company sent your Mother?
Never very much fun watching a family split up over these kinds of things. Let’s see if we can help sort out what is happening before the damage is permanent.