Bullying has always been a problem encountered during childhood and adolescence, but we all know it’s on the rise.

Enter the newest form – cyberbullying – whereby children and teens deliberately use digital media to disseminate false, embarrassing, or just plain mean messages or pictures about one person to others. The American Academy of Pediatrics calls cyberbullying “the most common online risk for all teens.”

Children of all ages need to understand that the Internet is not a “safe” place, and that it’s a public forum. Even if you delete a message or photo, it actually continues to exist in cyberspace.

All parents need to discuss Internet safety and the problem of cyberbullying with their children.

This is what I call the “front door rule”: Tell your child that if he or she writes an email or text, or posts something derogatory about another person on social media, to think before they push “send.” If they wouldn’t want to post the information on their front door, they should stop, think and change – or forget about – it.

Dr. Sue Hubbard is a pediatrician and co-host of “The Kid’s Doctor” radio show.