Finally, Michael Phelps has explained the reason behind his son's unusual name.

When “Boomer” Phelps was born in May this year to US swimmer Michael Phelps and his wife Nicole Johnson, no one batted an eyelid at the baby’s name.

It seemed comparatively normal, compared to some of the celebrity’s-babies-names we are accustomed to hearing. (Ahem, Gwyneth Paltrow, ahem)

But when Michael Phelps’ already impressive profile (and did someone say back muscles?) shot to fame at the Rio Olympics last month, baby Boomer came along with him.

Boomer was prepared.

The now four-month-old already had an active Instagram profile prior to the Games. But all of a sudden the little man was in demand.

(Especially after that footage of Phelps running up the stands to kiss Boomer, as Johnson and Phelps’ mother looked on. Phelps had just won his 20th gold medal. Hearts melted. Boomer looked unimpressed. Got to give it to him.)

A photo posted by boomer phelps (@boomerrphelps) on Jul 6, 2016 at 11:44am PDT

Now, with a total of 684,000 followers, baby Boomer has a lot to answer for.

And, considering he’s not yet taking interviews, he’s seemingly permitted his father to speak for him.

Phelps appeared on The Tonight Show With Jimmy Fallon on Thursday and answered the one question fans have been, just recently, very interested in.

“Why ‘Boomer’?”

“We heard the name, and we didn’t want, like, a normal name,” he told Fallon. “And I brought it up to Nicole and she was like, ‘Oh, that sounds kinda cool.'”

“Boomer, like boom boom — we didn’t know either,” he laughed. “We had no second option — once we picked that, we were like, ‘Yeah.’ I mean, he’s definitely gonna be the cool kid.”

Ummm… He’s already best friends with Jimmy. “Cool” is an understatement.

A photo posted by boomer phelps (@boomerrphelps) on Sep 1, 2016 at 5:15pm PDT

He’s also got that famous Phelps’ stare down pat.

There’s no stopping baby Boomer. (And who would want to?)