Hanson Reveals Which Brother Originally Came Up with the Phrase 'MMMBop' While Making Their 1997 Hit (Exclusive)

Isaac, Taylor and Zac Hanson reflected on making the chart-topping single in PEOPLE's new video series, 'My Side'

• Hanson is reflecting on the making of their 1997 hit, "MMMBop"

• The brother trio appears in the inaugural episode of PEOPLE's new series, My Side

• In the video, the band reveals who exactly came up with the titular phrase
  

Nearly three decades after Hanson released "MMMBop," the brother trio is looking back on the making of their signature hit.

In the inaugural installment of PEOPLE's new video series My Side, Hanson brothers Isaac, Taylor and Zac get nostalgic about creating the chart-topping 1997 pop hit — and who exactly came up with its iconic and unique title.

Before "MMMBop" was its own song, the band reveals, the memorable hook ("Mmmbop, ba duba dop ba / Du bop, ba duba dop ba / Du bop, ba duba dop ba du") was originally meant to be featured in the background of a different song, "Boomerang."

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"It goes, 'Bing- bang, hit me like a boomerang.' It's lots of bings," says Zac, 39, of the track, released on the band's 1995 demo album of the same name. "And I don't know why we would think something so complicated would be a good addition to that other song, which is also very complicated."

According to Taylor, 41, "It's hard to say who literally said, 'Mmmbop,'" but his brothers disagree.

"Taylor probably sang it first," recalls Zac. "I was probably coloring or something. I mean, I was little. I was like 7, 8 when 'MMMBop' was written. It's not like I wasn't there, it's just, I was probably just being me."

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Isaac, 43, says, "My memory is pretty good for that time, and if my memory serves me correctly, the three of us walked out of the control room where we were working, and then went around the stairs, in an area where there was a little bit more reverb sound in that stairwell, and we were just singing."

He adds, "It's very possible that Taylor said the first idea, like, 'How would you scat to this?'"

Released as the lead single off the band's debut major label album Middle of Nowhere, "MMMBop" reached No. 1 on the Billboard Hot 100 and topped the charts in over a dozen total countries.

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Elsewhere in the video, they open up about how it feels to perform "MMMBop" today.

"'MMMBop' is a song we really did write. We really did feel it, and it became hugely successful. And every time it was, it was an affirmation of that," says Taylor. "I really feel kind of a real gratitude for the fans that have seen it for what it is and that have listened to a lot more songs than 'MMMBop,' but I'm always proud to sing that song."

Zac explains, "Performing is very much about the audience, and the audience is still incredibly excited to hear that song. And so that makes it fun every time. What is really not fun is to listen to anyone sing the lyrics incredibly wrong and be like, 'I love that song. Scooby boop ka goo bop. Scoop doo.'"

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For Isaac, performing "MMMBop" live comes with a personally emotional reaction — especially during the band's 2018-2019 String Theory Tour, where they played the hit song with an orchestra.

"I think every single night I got teary-eyed when the lyric says, 'So hold on the ones who really care, because in the end they'll be the only ones there,'" he says. "Every single time it hit me that amongst other things, here are all these people, and they're here in the room with you, and in a sense, you're singing a song about them and who they are."

Hanson recently released Underneath: Complete, an extended version of their 2004 album Underneath. The trio is currently performing the album on the Underneath: Experience Tour, a 12-city trek of two-night stands — where they perform acoustic on night one and electric on night two.