The couple made this request at the festival, which was run by non-profit Project Healthy Minds in New York this week.
This saw them take part in a panel discussion with US surgeon Vivek Murthy, which was moderated by Carson Daly of NBC. Daly has spoken previously about his struggles with anxiety. It was also co-ordinated by Harry and Meghan's Archewell Foundation.
Having revealed that they had spoken to parents who had lost children to mental health issues, linked with social media, Harry called on social media companies to "stop sending children content you wouldn’t want your own children to see".
Meghan Markle also added that she and her husband have been working behind the scenes to find ways in which social media can be "safer, better and more positive". They have also discussed this issue with tech executives.
"People are getting hurt – and people, specifically children, are dying", Meghan continued. "A year ago we met some of the families, not all of them. At that time, it was impossible to not be in tears as I’m sure so many of you have been today hearing these stories".
"As parents, our kids are really young – they’re two-and-a-half and four-and-a-half – but social media is not going away", the Duchess of Sussex added. "I think by design, there is an entry point that is supposed to be positive, in creating community and something has devolved, and there is no way to hear that and not try to help these families have their stories be heard".
Harry and Meghan have also urged social media companies to amend their policies regarding content moderation, and tweak apps, which can be addictive to youngsters.
This discussion took place yesterday on World Mental Health Day (October 10).
The couple have been outspoken about their previous experiences with mental health.
