A six year old is making an estimated $11m a year as a toy reviewer on YouTube

"Ryan, the 6-year-old "host" of Ryan ToysReview, a popular toy-review channel on YouTube, is also reportedly a multi-millionaire.
A family-run YouTube channel, Ryan ToysReview generated around $11 million in pre-tax income in 2017, according to Forbes' annual list of the highest-earning YouTube celebrities.
The raw estimate of $11 million tied Ryan ToysReview with the YouTube comedy stalwart Smosh for eighth place on the Forbes list."
Source:  The Independent, 10th December 2017