AMNA NAWAZ: A new investigation looks at the disturbing world of so-called kidfluencers and the moms who run their accounts.

One in three preteens say being an influencer is a career goal, but the reality poses serious risks to underage girls.

Stephanie Sy looks at those concerns.

STEPHANIE SY: Instagram doesn't allow children younger than 13 to have their own accounts.

So what we're seeing is parents of kidfluencers set up and manage these accounts.

Posting content of girls can be lucrative.

Instagram makes it possible to have paid monthly subscribers.

And kids' apparel brands will pay thousands of dollars for a single post of a kid modeling, say, their dance leotards.

But what might seem innocent photos to a mom may read differently to a man or a pedophile.

New York Times reporter Michael Keller analyzed data from 5,000 of these mom-run accounts as part of a New York Times investigation, and joins me now.

Michael, thank you for being here.

I mean, the headline of your report really sums up the risk: "A Marketplace of Girl Influencers Managed by Moms and Stalked by Men."

What did you find about how prolific these accounts are and why so many moms are into this?

MICHAEL KELLER, The New York Times: My colleague Jennifer Valentino-DeVries and I wanted to look into this world of child influencers.

And, as you said, they often are too young to have accounts of their own, and so they're run by their parents.

They got into them for a variety of reasons.

There was a range from dancers and gymnasts who wanted to get free or discounted leotards in exchange for photos modeling the apparel.

A lot of parents said that social media was the way they could assure a good digital resume for their child's future and maybe even help pay for college or gain opportunities working with sought-after choreographers.

On the more extreme end, your aspiring models, some had their own subscriptions, both on Instagram, where they would charge up to $20 a month for more photos or chat sessions with the child, or on other platforms, where the monthly cost went as high as $250.

STEPHANIE SY: So your report also found that a lot of the followers of these accounts are men.

Are they driving these accounts' popularity and their profits?

MICHAEL KELLER: So we did an analysis looking at the follower size of these accounts and the percentage of men in that audience and did find a correlation that, as the audiences got larger, there were more men in them.

Now, some parents and pretty much all the parents we spoke to said that men following them and posting inappropriately was a really big problem.

Some of them said that the first thing they did when they woke up in the morning was block followers and the last thing they did before they went to bed was block followers.

They often post inappropriate or even proposition the girls in the comments below the photos.

They do block them, as I said, but a lot of them ran into issues where, if they blocked too many, Instagram would start limiting their ability to either follow new accounts or to block even more.

One parent said: "I can't believe this.

I have reached my limit for the day of blocking creepy men."

STEPHANIE SY: Michael, I just want to show our viewers an example of what you're talking about.

The New York Times in your investigation doesn't show the actual post, but you describe what the post showed, a 9-year-old in a golden bikini lounging on a towel.

And then you show the comments section full of sexually suggestive remarks.

But, Michael, it doesn't stop at the comments in every case.

You describe a world in which the girls are sucked in to the sort of Internet underworld of sexual predation.

MICHAEL KELLER: Right.

And that was what was truly disturbing in what we found.

Beyond the suggestive or predatory comments, some parents actually received threats from some of the (AUDIO GAP) online.

They would reach out and accuse them of exploiting their child and threatening to contact their school or their family and friends and seemingly expose them, because it is worth noting that in -- photos of children in dance conventions are normal within that context.

But within the context of the Internet, people bring to them in some cases their own skewed points of view.

And so these men were trying to, seemingly with threats of blackmail, cause a lot of actual harm to the families.

STEPHANIE SY: So, it occurs to me, Michael, that this is not just an investigation into risks that girls are taking online, but a story about parents who are making the decision to put their girls at potential risk of ogling, at the very least.

What is the biggest takeaway for moms who are thinking of letting their daughters become influencers?

MICHAEL KELLER: So, as we said, Instagram does allow parents to run these accounts for them, even when they're below 13.

But what we found was that it is very hard to do so in a safe way, and that it may take hours every day of blocking creepy or possibly predatory men from interacting with the account.

And the real-life threats that this could lead to, maybe -- we heard stories of strange packages showing up at people's doors, and could go from the online world into real life and affect your family, was a really strong takeaway for me.

STEPHANIE SY: Michael Keller with The New York Times, thank you for joining the "NewsHour."

MICHAEL KELLER: Thank you so much.