Call a time-out. If you see your child hitting, biting, or spitting, stop the behavior immediately. Try to speak calmly, but if your child doesn't listen, take her aside and say, "You're out of control. You need a time-out to calm down."
Don't demand an explanation. Asking a child why he did something wrong implies that there may be times when it's okay to be mean. That's not to say you shouldn't look for a cause. If your kid pulled his friend's hair because his pal was hogging the swing, do help them take turns after you've dealt with the hair-pulling. "This shows kids they live in a just world and that if they tell you about something unfair or upsetting, you'll try to fix it," explains Dr. Dix.
Try not to lose it. Some kids believe that any kind of attention beats no attention at all. So if you freak out when your child does something wrong, she'll be intrigued ("Wow, Mommy went crazy!") and she'll have incentive to act up again.
Tie kids' actions to other people's feelings.Toddlers have a limited understanding of how their behavior affects others. Your child needs to know how his friend felt when he got kicked. Say, "That hurt Sam and made him feel bad." Tell him you know it's hard to share, but kicking someone is not the right thing to do.
Help your child calm down. Toddlers get just as upset as adults do when they lose control. After a brief time-out, talk to your child in a comforting and compassionate way. Say, "I know it feels terrible to get so upset and make someone else feel bad." This helps kids understand their emotions and learn to label them.
Don't force kids to include others. Sometimes, your child may act like a bully by excluding other kids, but it's actually a normal part of social development, says Dr. Carr. "In a small group, toddlers get their friends' approval when they tell another child he can't play," he says. "By excluding someone, your child is saying 'You're special' to the kids she's already playing with." The solution: Find a time when your child and her left-out buddy are apart and let her know that you saw what happened -- and that excluding someone isn't nice.
Start teaching problem-solving skills. Do make it fun: Use imaginary play to help your child learn positive ways to resolve a sticky situation. You might pretend to be another child who has taken your toddler's favorite toy. Teach him how to use his words ("That's my toy -- please give it back"), and if that doesn't work, tell him he should ask an adult for help. Act out these scenes often so that the lessons sink in. Just keep trying -- and soon you'll have a really sweet kid.