The president of Fullscreen, a huge global network of content producers and brands on YouTube, had a mission before visiting this year's Web Summit: he wanted to meet a toy reviewer and his son deep in rural Ireland.

Ezra Cooperstein, whose business was valued at up to $300 million when telecoms giant AT&T and the Chernin Group bought into it last month, spent the Monday before the summit on a long drive to see the father-and-son toy review team in the hope of signing them up.

The toy reviewers, who post under the name of Coolpinsky and are known to their fans as Arcadius Kul and Sammie, have posted videos that have been viewed 297 million times and have more than 278,000 subscribers or fans.

Mr Cooperstein mentioned his visit to the unnamed toy reviewer during the course of a talk at the summit about how individuals were producing content that attracted global audiences.

After his talk, he declined to tell The Irish Times who was behind the hugely popular reviews or where they were. "We would love to do a deal with them but they are very sought after by our competitors too," he said. "They are doing really well, so we wanted to meet them, talk with them and learn from them."

Dubliner Jonathan Cloonan, director of partnerships at Group M, the world's largest media company, said these reviewers were "Ireland's biggest YouTube star that no one has ever heard of".

“My job is to match YouTube stars with brands and broker deals. They are the next big stars and they are the next big brands themselves,” Mr Cloonan said. “I am in my late 20s so people my age might not have heard of them, but these are the Eva Longorias to the next generation.”

Mr Cloonan, who also spoke at the Web Summit, said North America had most of the world's biggest YouTube stars but "the democratisation of the web means YouTube is a distribution platform where anyone can he a star."

For example, he said the world's biggest YouTube star was a 25-year-old from Sweden who made millions a year reviewing video games under the name of PewDiePie.

Arcadius Kul in its YouTube profile page gives little away about itself other than they love toys and want to review them in a family-friendly way. It describes itself as “a story about a father and his son Sammie. They have a mission to hunt for toys, to explore Surprise Eggs, to have a lot of fun, to put a smile on your face.”