A more thorough explanation:

The family-automobile doctrine, also known as the family-purpose rule, is a principle in tort law that holds the owner of a vehicle responsible for any injuries or damages caused by a family member's negligent driving. This means that if a family member causes an accident while driving the owner's car, the owner can be held liable for any resulting harm.

For example, if a father allows his teenage son to use the family car and the son causes an accident due to his reckless driving, the father could be held responsible for any injuries or damages caused by the accident.

It's important to note that many states have abolished this rule, and it may not apply in all situations. Additionally, the family-automobile doctrine is often closely related to the family-purpose rule, which holds that the owner of a vehicle is responsible for any harm caused by the vehicle's use for family purposes.