Before parents can figure out how to respond to the issue of their children's friends, they have to understand themselves, their role, and how their children develop.
"A parent's path is to help kids learn to take responsible care of themselves. I look at everything through that."
A big part of that is understanding the role of connections.
"Connections underlie everything," Volcani says. "It's why Tom Hanks named his volleyball Wilson."
The ball was Hanks' character's only connection in the movie "Cast Away," where he found himself alone on an island after a plane crash. The relationship he had with that ball and the desolation he felt after it floated out to sea were accurate reflections of how crucial connections are in life, Volcani says.
For young children those connections are to parents, siblings, extended family, maybe pets. Once kids enter school, the connections will be to teachers, classmates, neighbors, members of their Girl Scout troop or Little League team. And friends.
Here is where parents have to factor in another concept.
"Now, we get to limits," Volcani says. "One, the limits must be age appropriate and expanding and, two, you have to, have to, have to foster autonomy within the limits set."
For a young child, he uses teeth brushing as an example. In the parent's domain is that daily brushing of teeth is mandatory. In the child's domain might be what kind of toothpaste or toothbrush to use.
For the older child, he tells the story of how his mother, once he turned 13, told him she wasn't going to fight with him about his messy room anymore. She moved it from her domain to his. With limits. He couldn't damage the room by putting holes in the walls, he couldn't let things get so bad that she could smell odors coming from the room, and he had to keep the door closed.
"Development is more and more about putting things in the child's domain," he says. "So, now, whose domain are friends in? The friends thing is very tricky."
When your young child has a friend you don't like, unless that kid is destroying property or stealing from you, Volcani says to stay out of it. You could take up the annoying behavior with the offending child, or that child's parent, if you're close enough to the family.
Maybe you're worried the back-talking or mean or selfish or lazy behavior in the friend will rub off on your child.
"You want to err on the side of belief in the goodness of your child," he says. Instead of restricting the friendship, first try explaining to your child the concern you have about the friend's negative behavior.
"You tell your child, 'If I don't see you taking care of your (behavior), then I'll have to go to the next level,' whatever that is."
Things get even trickier with older children. Volcani cautions parents of teenagers not to fool themselves.
"Don't set a law you can't enforce," he says of the temptation to forbid certain friends. "It's an illusion that you can control who they spend time with."
They will manage to see those friends at school or wherever. Better to open up and be honest.
"Just say, 'I get scared when you're with so-and-so. I know very well he's a substance abuser, smoking marijuana and drinking. I feel very awkward telling you whom to associate with. That seems very controlling. However, that being said, I'm worried that you're in a bad situation and all kinds of horrific things can happen.' Then wait and see how your child responds."
Volcani says you might be met with denial of all that you know to be true, and you might need to reconsider limits. Or your kid might agree with you, express concern for himself but also worry that he is abandoning his friend by not hanging out with him or her anymore.
That can lead to a deeper discussion about ways your child can help the friend. The bottom line, Volcani says, is that these situations often are opportunities for parents to provide their children with more lessons in learning to take responsible care of themselves.