The family purpose doctrine holds which group responsible for negligent acts?

The family purpose doctrine is a legal principle that holds parents responsible for the negligent acts of their minor children while those children are operating a vehicle or engaged in an activity under the family's purpose. This doctrine is based on the premise that parents have a duty to supervise and control their children, especially when the child is using a vehicle that is owned or provided by the parents for family purposes. This establishes an inherent liability on the part of the parents for the actions of their children, reinforcing the idea that the family unit has collective responsibility when it comes to safety and conduct.

In contrast, the other groups mentioned do not fall under this specific legal doctrine in the same direct manner. Spouses may have separate legal implications depending on the situation but are not held responsible in the same inherent manner by this doctrine. Siblings may have some familial obligations but do not typically bear legal responsibility for each other's actions under this doctrine. Grandparents, like spouses and siblings, are not covered by the family purpose doctrine regarding liability for the actions of grandchildren.