When you buy a car/truck, the insured car/truck is collateral. In this case, you have no collateral. It's not your house.
-Gotcha
You may be your parent's age, if and when, you inherit whatever might be left within their estate.
-At this rate.... Maybe sooner
If they are like most folk, they will need every cent for their own retirement:
-Dad was bad with money. Mom didn't work. Therefore I am their retirement funder..
Medical expenses and extended care:
-Brother takes care of that portion.
None of us know what the future holds.
-Is exactly why i play the lotto.
And God forbid, they might have to take care of you, if you became injured or got sick.