It sounds like your mother is doing what she needs to do in order to care for your dad like he needs. (If that makes sense...)
I’ll wave at her as she flies over, since we’re right in the flight path for McCarran! LOL! Coming or going!
Does your dad have a “med-alert” (bracelet or necklace) for those times he’s alone? That would be a good investment, if he’s alone in the evenings, even once in a while.
Your mother should be able to get the information from the 2008 Medicare book.
Is “Med-Alert” the device that signals a security company? He doesn’t have one of those, but he has a “dog-tag” with his name, address, and phone number, and the information that he’s an Alzheimer’s patient. His physical health is very good, so they’re not concerned right now about his becoming ill. He just forgets to lock the door and turn the stove off!