Cliff reported that the driver was 20 years old.
An adult. A young one indeed, but still an adult. Not Mommy and Daddy's responsibility by law, anyway.
That depends on who the car is registered to. If it's in Mom's and Dad's name they can be held responsible. There have been conditions where adults up to age 25 and their parents have been sued (and the victims won) because these so called "adults" were still living in the parents home and the parents were supporting the "adult."
I would imagine a lot of this varies by state too.