For a YouTube channel you've likely never heard of, "Little Baby Bum" sure holds a bunch of world records.
The channel, which has 12.9 million subscribers, features animated animals performing nursery rhymes and educational songs for children.
One of their videos, a 54-minute-long compilation of children's songs entitled "Wheels on the Bus," has been viewed more than 1.9 billion times, the world record for most-watched educational video, the most-viewed nursery rhyme, the most-viewed children's music video and the highest watch time of any clip on the site.
"We make nursery rhymes," co-founder Derek Holder told Inside Edition, laughing. "There you go."
"Little Baby Bum" was the couple's nickname for their daughter, who inspired the channel. In 2011, Holder wanted to play her nursery rhyme videos, but when he turned to YouTube, he said he was disappointed by the quality of the clips.
"I started looking at the numbers of these terrible videos and seeing there’s 10 million, 20 million, 30, 40 million views," he recalled. "I couldn’t believe how many views some of these videos were getting."
So Holder, who has a background in search engine optimization (SEO), suggested to his wife that they create their own video for "Twinkle Twinkle Little Star." His wife was reluctant at first, but he eventually persuaded her.
"We thought... 'We’ll call the channel Little Baby Bum, and her favorite song is 'Twinkle Twinkle Little Star.' We’ll stop there," he said, joking: "It was as scientific as that."
But after seeing the response from viewers, they realized they couldn't stop. Even his wife agreed.
"She kinda quickly came around after seeing the numbers for herself," he said.
So they got to work, with his wife devising characters and ideas for the visuals as Derek created the traditional tunes — but with a twist.
"The philosophy from day one was always pretty much keep the lyrics of a well-known nursery rhyme pretty much as it is... but we can go as crazy as we like the visuals," Holder said. "So that’s why in the early ones we have "Baa-Baa Black Sheep" in, you know, in outer space."
They've since branched out with original songs. While everyone knows "Twinkle Twinkle Little Star," he says not everyone's heard of "Potty Song," which includes the line: "I like to sit down on the potty, so much fun."
"We all go through exactly the same thing, highs and lows of everyday life," he said. "We just try and incorporate that really into what we’re doing.
"And of course, the learning as well — simple ABC, 123 stuff is really important... It’s not the deepest of philosophies, but it seems to work."
The couple now produces videos in seven different languages. They're the 7th most viewed YouTube channel in the world and the 79th most subscribed.
"It still staggers us," Holder said.