My three-year-old son is constantly taking off his trousers, and running half-naked around the house. He often engages in, well, other forms of activity too. “Look, mommy, it’s getting bigger. How did he do that?” asked my five-year-old daughter (who has had her own episodes of self-exploration), about her brother’s actions. It was a good question, making me realize that my children’s genital curiosity was something I couldn’t simply ignore.

What does self-touching mean to a preschooler? Playing with one’s genitals or self-stimulation is very different for young children than it is for adults, because it’s not necessarily accompanied by sexual thoughts and fantasies, says Cory Silverberg, a certified sexuality educator in Toronto. “It isn’t sexual in the way that we think of sexual.” And not only is it absolutely normal, it’s perfectly healthy, he says. It also provides parents with great opportunities to educate their kids about physical health, body image and what Silverberg terms “streetproofing”: teaching your kids that it is okay for them to touch themselves, but not to touch others or for others to touch them.

Why do they do it? While there’s no formal research about why preschoolers touch themselves, we can take some educated guesses, says Silverberg. It can be soothing, relaxing (especially before sleep), a good distraction (particularly if the parents are arguing, or the child’s soother has been taken away), and it feels good. Children may also do it if they feel anxious, or simply because they’re curious. Here are some guidelines about how to respond to your child’s budding interest in her own body.

1 talk early and talk often

Laura Wershler, executive director of Sexual Health Access Alberta, stresses the importance of getting parents talking to kids about sexuality-related issues. The message is threefold: You can have an impact on the sexual health of your child; you don’t have to be an expert; and you can do this.

“Research indicates that talking to kids early and often about sexuality promotes healthy sexual development and reduces risky adolescent sexual behaviour,” Wershler says. While it may be premature to talk about safe sex practices with your four-year-old, helping your child to understand and appreciate his or her body is a vital first step to sexual health. “There’s no one big talk. There’s lots of little conversations,” says Wershler.

2 react calmly, honestly and openly

That means simply responding to their questions and actions without overreacting, and acknowledging that it gives pleasure. “Don’t treat a behaviour differently because it is attached to sexuality or because as adults we identify it as sexual,” suggests Silverberg.

3 set boundaries

Explain to your child that touching herself is something that is done in private, and then explain where it is okay to do it, such as in the bedroom, or in the bath. When you catch her in the act in public places, first try to distract her. If that doesn’t work, give her a gentle reminder.

4 teach him about his body

You can begin your child’s sex education by teaching him the proper names for his body parts. Bathtime provides a great opportunity to do this. You could, for instance, say, “Now let’s wash our belly, our knees, our scrotum….” That way, you give equal importance to each body part. If you make up names or disregard certain body parts, “you send the message that there is something wrong with [those body parts] or that they should be ignored,” Silverberg explains.

5 encourage good hygiene

Simply explain to your child that her hands should be clean before touching herself. For instance, “One thing we need to do is always wash our hands [before we touch ourselves]. If you don’t, you could get dirt in your vagina, and that could hurt,” explains Silverberg.

6 call the doctor if you’re concerned

Parents who are paying attention to their children’s development will likely notice if a behaviour is compulsive, says Silverberg. There’s a big difference between children touching themselves regularly, and doing it because they can’t stop. If you’re worried, speak to a doctor.

Diana Ballon is a Toronto-based writer and editor who specializes in women and children’s health issues.

Keep reading to find our more about how to talk to your preschooler about sex.