A nonprofit watchdog group has filed a deceptive advertising complaint with the Federal Trade Commission against what it calls "kidfluencer" YouTube channel "Ryan ToysReview." It claims the channel is deceiving preschoolers in early development who can't tell the difference between advertising and organic content.

Since its launch in March 2015, "Ryan ToysReview" has gained 21 million subscribers and more than 31 billion video views, according to statistics posted on the YouTube channel.

Truth In Advertising (TINA) says it analyzed every video "Ryan ToysReview" posted between January 1 and July 31. TINA says that in nearly 90 percent of the videos, it found references to at least one product recommended for children under 5 years old.

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"Some of these videos are sponsored, some are not, and some take the form of other supposed organic content on the channel but are nevertheless ads. And while adults may be able to spot the marketing content, the target audience — children under the age of five as TINA’s investigation shows — cannot," TINA said in a statement. It went on to say that for the targeted age group, there is no adequate advertising disclosure.

TINA claims that companies including Walmart and Nickelodeon have sponsored endorsements on the channel's videos, but that these endorsements "have the look and feel of organic content."

Ryan ToysReview released this statement from Ryan's father, Shion Kaji:

“The well-being of our viewers is always our top priority. Creating content that is safe and appropriate for our young viewers and their families is very important to us. We strive to provide quality, engaging content including skits, family challenges, science experiments, cartoon animations and more. We strictly follow all platforms’ terms of service and all existing laws and regulations, including advertising disclosure requirements.  As the streaming space continues to quickly grow and evolve, we support efforts by lawmakers, industry representatives, and regulators such as the FTC to continuously evaluate and update existing guidelines and lay new ground rules to protect both viewers and creators.”

A search of videos on the "Ryan ToysReview" channel shows that some videos, like this one, do contain warnings that they are paid advertisements.

Members of Congress sent a letter to the FTC in August calling on it to investigate "Ryan ToysReview" for what it called "unfair and deceptive practices."