As most voluntaryists will readily discuss, a stateless society would still have courts.
I definitely understand where you're coming from in your article here, Larken, and I believe this is compatible with my own perspective on the matter so long as the courts make no such distinction regarding competence; after all, for somebody to be in court arguing for their self-ownership, they clearly must be competent enough. When I talk about the issue, I'm talking about the legality of it. Surely within a family, even a peaceful parenting family, people will technically violate the NAP. A brother will pull his sister's hair with a smile. A mother will yank her son away from an open sewer hole. A husband will lift and carry his wife against her will. It happens, and it's generally not a big deal.What would become a big deal, however, is for the courts - and therefore the security market - to back up the use of force against a person to protect that person from his/her self. That's when this becomes a downright insidious matter. That's where you find true oppression; when the use of force to protect somebody from his/her own foolishness is not only legal, but legally backed.
Personally, I would forcibly interfere if my child were about to commit suicide. I just recognize that I would be violating the child's rights, and it cannot be a legal matter; I shouldn't be able to send the kid to a padded room over it, and if the kid wishes to sue me, that's shitty, but ultimately, my behavior wouldn't be ethical