Years ago, my parents were traveling in their 5er from PacNW heading to see us in GA, when he had a stroke in Elko, NV. My oldest sister and her husband hit the road and drove down to pick them up when the Hospital released him.
They had to sell both the Truck and 5er and bought a converted Van that my mother could drive. She wasn't comfortable in a big vehicle, so they traded it for a smaller sedan and she did all the driving after that.
If anything happens to my DH while we're on the road and he can't drive, we would also contact one of the kids to help get us back to Homebase.