Transcript for What teens wish parents knew about the 'constant pressure' of social media
Now to our "Gma" experiment taking a closer look at how social media afaxes teens. ABC's Deborah Roberts sat down with a group for a candid conversation and what they didn't know, their mothers were watching behind the glass, deb. That had to be something. Good morning. Reporter: Good morning. It's an eye opener if you're a parent or anyone involved in the life of a teen girl, experts say they're suffering from depression and stress at higher numbers than ever. Toss in social media and coming of age has never been harder. Every girl thinks they have to be better than the other girl. There's a constant pressure I guess with everybody. Sometimes your stomach is fat. Wait, is it? Reporter: Teen girls offering details about their struggles. We set up an experiment in new York and invited a few to come and sit and talk with us but unbeknownst to them, on the other side of this glass will sit their moms right here, listening and learning about their daughters. Reporter: But in the adjoining room they only see a plain old mirror. How many would say stress is a big problem in your lives? Your hand went up big time. Reporter: The talk quickly turns to their biggest challenge right now. Social media. Research shows that nearly a third of teen girls are suffering from anxiety. We wondered if their lives on many line adds to that problem. How big of a part of your lives is social media? I love -- Very big. Snapchat. My mom has my Instagram password so she'll see things before I do and be asking the questions. Reporter: Questions she says about who she's following online. All these girls are deeply plugged in. Instagram, Facebook, Snapchat. 71% of all teens use more than one social media site. A way of expressing themselves. Online they look happy. Yet these girls say there's a dark side. A lot of criticism towards me on social media but I choose not to pay attention to it. Cyberbullying translating into real life then you have people that are taunting you while you're right there. Reporter: If somebody says I don't like the way you look. I think I look great so who cares what they say but then it's like somebody just said that to me. Are you kidding me. I don't hate my body but I feel like there's room for improvement all the time. Reporter: The honesty about their insecurities tough for one mom behind the mirror. A lot of my friends think I'm anorexic because I'm skinny and stipes it can hurt but got to grow tough skin. Used to get bullied because I had a unibrow, wasn't the skinniest girl in do you hide anything from your mom on social media? Why don't we just talk to your moms now because your moms are here. You know. The girls stunned that their moms just heard how they navigate their lives with so much instant feedback. A problem that didn't exist years ago. What surprised you most about anything you heard from your daughter? It's so different, the struggles that the kids are going through now. I believe if parents engage their kids more they get more out of hem. She's very emotional so she lets things get to her easily. One day she took a nap and checked her phone. She gets this text message why don't you shave your arm you Indian bleep and immediately I just -- the steam just came out of my ears. Reporter: With parents so often in the dark, these moms getting a powerful lesson in the lives of teen girls. These girls are gorgeous and they're smart and they're full of anxiety. Ooh. What an eye opener, deb. Also joining us is parenting expert, Dr. Logan levkoff. Thank you, thank you for wanting to have this discussion. I bet you had a conversation with the moms off camera after. What did they say? What surprised me is that these are moms who are really involved in their daughters' lives and know them well. They were surprised at the intensity by which they were trying to juggle their live, their usual teen lives with peer pressure and cyberlife which is a whole different thing where they're being judged and criticized. They were really surprised at how difficult that is. We're living there. Our girls are 15 and 12, and Logan, Ali does a good job of monitoring the social media. Is that a good thing to do. Absolutely. This is a generation of technological Guinea pigs. We don't know long-term impacts but our kids are cure rating their personal brands 24 hours a day. Think how exhausting that is. Never a shutdown time. If we weren't at school or socializing coco shut the door, cool off, get perspective. They don't have that anymore. Their down time is with their phone. That's not down time. That's very much on time. It's a generational gap as you're discussing and, you know, for moms they didn't have to go through this. How do they talk to their daughters. They try to keep them close and connected and said the most important thing and these were really, really impressive moms try to make sure they have a balance and know they're involved in their lives. For some of hem church is important an a couple have gotten involved in pageants. Things other than the cyberworld to keep them connected to something real. Need advice here. What do you do if you find a secret account. The reality we don't know everything our kids are doing online but we can have certain expectations and guidelines and responsibilities for them. That's our job as parents. We're not just their friends or not just the authority figure but there to also be respected and to say, look, these are the consequences. If I find out then there is a reaction. We're not -- it's not an idle threat. I might be annoying and you might be upset but there's probably relief in it too they can be forced to 14u9 down. Give us advice on how we can build our daughter's self-esteem. Talk about their character, how they contribute to the world. Their achievements and strengths, they're under the impression that phones represent freedom. But the truth is there's nothing more that feels like an intellectual or emotional prison. Everything they do they get defined by. Adolescence is about making mistakes. We should let them make them but we can't now. Find things they can do that are not just related to whether they look good. They are worried about how many likes they're getting and some are involved in extracurricular things, of charity things, all kinds of things that like they can judge themselves by that have nothing to do with their looks and the things that they see online. Though they may not give this off, they want structure. They do, absolutely. They want to talk too. One of the girls said I'm a big '80s fan because people used to talk to each other. They are relieved with structure. They need it. We'll talk to fathers and sons in the same kind of way. Very different thing that the boys are concerned about. You'll want to hear this one. We'll have more resources from our good friend here on our website. So over now to ginger.
This transcript has been automatically generated and may not be 100% accurate.