Most parents hope their children will make friends with other kids and treat them kindly.

But when parents suspect that things aren't working out that way, it can be hard to know how to react.

"If your child is being picked on, there's a lot of information out there" about what to do, says one Bay Area mother who is worried about her own child's mistreatment of friends, "but I really don't see anything for people in my situation."

Pat Mitchell, executive director of Silicon Valley Faces, a nonprofit organization that runs violence prevention programs for children and adults, says parents should realize that any child could become a bully.

"Many parents just can't fathom the fact that their child would ever be a bully," she says. "Parents really do need to talk with their children, and not assume children will intuit through their own behavior that bullying is not OK."

Bullying can take many forms, including physical threats, verbal intimidation or emotional humiliation, and can happen online as well as in person. The often tragic consequences of kids and young adults bullying each other has been making headlines for years, in too many stories about children who feel bullied and powerless suddenly showing up at school with guns. Or about victimized children who take their own lives to avoid facing more mistreatment from peers.

Parents everywhere are sickened to think that such a thing could happen to their own children. And they are just as frightened to imagine that their own child could be doing the bullying.

"Bully," a new documentary by filmmaker Lee Hirsch (opening April 13 in San Francisco) provides one opportunity for parents and teenagers to explore the topic together, from the standpoints of the victim and the bully. The film tells the stories of a handful of children around the country, portraying both their heartbreaking vulnerability and astonishing resilience.

Director Hirsch says he interviewed some parents of bullies who were unaware their children were mistreating others at school.

"After seeing the film ... parents will have more insight into what to look for and the questions to ask," he says. The film calls on parents and children alike to take action to end bullying. (Go to www.thebullyproject.org and clink on "demand it" to vote to bring a screening of "Bully" to your city.)

It's clear parents sometimes need guidance on this subject.

One Bay Area parent, who does not want her name used because she doesn't want her 10-year-old daughter to be labeled as a bully, says she's worried about the child's sporadically unkind treatment of other kids at school, dating back to first grade. Trying to stop the bad behavior -- which has included hitting another student and repeatedly acting mean toward friends -- has meant numerous talks with teachers, other parents and the school principal. The mother has read a lot about bullying and done plenty of soul-searching about the family dynamic. But the family is a loving one, she says, where meanness is not condoned; she's mystified about the roots of her daughter's behavior.

"I'm heartbroken," the mother says. "As a parent, you know relationships are of utmost importance, and you start thinking, 'Oh my gosh, is my child going to grow up to be a mean person? Is my child going to be a bully?' And whenever that word comes in, it's so upsetting.

"Your heart drops when you get those phone calls or notes saying your child is not being nice," she says.

The mother feels she has tried everything. But the problem continues, she says, and she's not sure where to turn.

The reasons children bully others are varied, says psychiatrist June Reynolds of Kaiser Permanente San Jose Medical Center's child and adolescent psychiatry division. Some bully others because they've been bullied themselves, either at home or school; others do so because they feel powerless or insecure. Reynolds and other parenting and child psychology experts say the key to raising children who don't bully is to foster empathy in them, because people don't mistreat those with whom they empathize.

"Many children are very empathetic, and seem to come by it more naturally," Reynolds says. "(With) other children, you do need to educate about that, and model that behavior."

Sociologist Christine Carter of UC Berkeley's Greater Good Science Center is author of the advice book "Raising Happiness: 10 Simple Steps for More Joyful Kids and Happier Parents" and teaches parenting classes (www.raisinghappiness.com). She says a first step to instilling empathy is to help children understand their own emotions, including giving them vocabulary for describing their feelings. So if a child has been aggressive to a friend, a parent can say, "Wow, you must have really been hurting to do something like that," she suggests, or "jealous" or "frustrated," etc. "You can say, 'It's OK to be jealous, but how you behaved was not OK.' " That gives the child a word for what he was feeling, lets him know that feeling bad is OK, but that mistreatment of a friend is not.

Kids need to understand their own emotions and how to respond appropriately before they can extend their understanding to others, Carter says. Children who have positive ways to assert themselves -- especially in the form of helping others or helping in their own households -- are less likely to assert themselves in negative ways, such as bullying, she adds.

"When we do something kind for someone, even something small, we feel powerful," she says. In some households, especially ones where parents or other adults take care of all the chores, kids feel "unneeded." Research shows that kids who are given responsibilities are less stressed out.

"Being needed promotes a sense of control and power," Carter says, but "the super-permissive, easy life does not."

Instilling empathy during infancy and early childhood is great, says Mary Gordon, founder of an internationally acclaimed educational program called Roots of Empathy, but it can be effective at any age. (The Toronto-based Roots of Empathy program is being introduced in the Bay Area this year, at five public schools in Oakland and one private school in El Cerrito.)

It can very powerful for a child, including tweens and teens, to hear a parent's story of something troubling or embarrassing that happened to the parent.

"For any parent to share with their child, 'I had a hell of a day today, and there was this person in the elevator who been nasty to me at work' -- to share the social and emotional dynamic with the child, the child actually becomes like father confessor. The child will actually say, 'Mom, did you think of this, did you say that?' To share the vulnerability is to allow genuine, authentic communication."

That, in turn, fosters empathy, which reduces the chance that the child will become a bully.

Contact Sue McAllister at 408-920-5833. Follow her at www.twitter.com/suemcal.

Resources for parents and teens

Common Sense Media information on cyberbullying: www.commonsensemedia.org/advice-for-parents
No Bully, a California nonprofit program for schools: www.nobully.com
Project Cornerstone, an initiative of YMCA Silicon Valley: www.projectcornerstone.org
Roots of Empathy, program for social and emotional learning in children: www.rootsofempathy.org
Silicon Valley Faces, programs to promote empathy and prevent violence: www.svfaces.org
U.S. Department of Health and Human Services anti-bullying information: www.stopbullying.gov

'Bully'
documentary

Opens April 13 in San Francisco; to learn more or to vote to request a screening in your city, go to www.thebullyproject.org.

Help your children avoid bullying behavior

One building block toward empathy can be talking with them about their feelings and emotions.
Model empathetic, compassionate behavior by treating children and others respectfully.
Share your own experiences of vulnerability with your children.
Provide consequences for bad behavior. If a child mistreats another, take away a privilege; if a child sends mean texts, take away his/her phone, for example.
If a child mistreats others, examine the family and school dynamics for signs that he/she is feeling mistreated or powerless.
Seek help from teachers and principals, other parents and mental health professionals, if necessary.

Sources: Dr. Christine Carter, Mary Gordon, Pat Mitchell, Dr. June Reynolds