Nine-year-old Ryan Kaji for the third year running has become the highest-paid YouTuber, earning $29mn from "unboxing" and reviewing toys and games on YouTube.
Aside from earning $29.5m from his "Ryan's World" YouTube channel, hailing from Texas, Kaji also earned an estimated $200m more from Ryan's World branded toys and clothes, including pyjamas from Marks & Spencer.
He has also signed an undisclosed, but potentially multimillion dollar, contract for his own Nickelodeon television series, reports The Guardian.
In March 2015, after watching other toy review channels and asking his mother, "How come I'm not on YouTube when all the other kids are?" Kaji, - described as a "child influencer" - first began making YouTube videos.
His family – who changed their real surname, Guan, to his on-screen surname, Kaji – now run nine YouTube channels.
Ryan's World was the most popular with 41.7m subscribers and 12.2bn views. Kaji's most popular video, Huge Eggs Surprise Toys Challenge, has more than 2bn views, making it one of the 60 most-viewed videos ever on YouTube.
However, Kaji and his family are now facing the threat of a US Federal Trade Commission investigation over allegations that videos' sponsors are not properly disclosed.
"Nearly 9% of the Ryan ToysReview videos have included at least one paid product recommendation aimed at preschoolers, a group too young to distinguish between a commercial and a review," a complaint from the consumer watchdog, Truth In Advertising, said. "These advertisements often depict unhealthy foods."
Benjamin Burroughs, an assistant professor of journalism and media studies at University of Nevada, Las Vegas, who studies emerging and social media trends, warned that there was a danger that other children were "being targeted by child influencers in ways that parents may not be cognisant of or aware of."
"As a child influencer, Ryan is being courted by companies to play with the latest toy so that other children can see it. But now, the child influencer himself has become a brand that is then being put into Walmart, and Target, and Amazon as its own force and influence," Burroughs said. "It's pretty shocking."
Burroughs said he became interested in the child influencer phenomenon after his own kids asked him to do the things that Ryan's family was doing. "I thought, 'Oh, there's something going on here if my kids are expecting our family to look like Ryan's family.' In Ryan's family, they're able to constantly consume content and products. They're opening up a new toy every day, and subsequently playing with that new toy every day, so there's this constant consumerism that's being embedded within these messages for children."
In total the top 10 biggest-earning YouTube stars took home a total of $211m, according to the Forbes business magazine, which on Friday published its analysis of their estimated earnings between June 2019 and June 2020.
In second place was Jimmy Donaldson, better known as Mr Beast, who earned an estimated $24m and was a new entry to the YouTube rich list.
Donaldson, 22, is known for stunts, including freezing himself in ice and giving away huge sums of money to strangers who compete in his challenges. He also makes money from selling merchandise and partnerships with brands such as Microsoft and Electronic Arts.
Reed Duchscher, Donaldson's manager, said: "The ideas are going to continue to get crazier, and he's going to continue to spend large amounts of money to up the production quality. I mean, he just tweeted out today that he has all these good ideas that cost $10m. And he's not wrong. He does."