Superfan Meghan Trainor Loses Her Mind When Dr. Phil Joins Her on Carpool Karaoke

Meghan Trainor says she's been waiting for years to help James Corden get to work on Carpool Karaoke, and Thursday night was finally her chance.

Even better, James concocted the best possible surprise, eliciting a reaction so pure and genuine there was absolutely no doubt that her super-fandom of Dr. Phil was absolutely true.

Actually there was no doubt after she revealed to James that she had just recently been to his show.

"You were on his show?" James asked.

"No, no. I was in the audience," she said. "For my birthday, my brother got me tickets to see Dr. Phil live and I went there and it was the greatest day of my whole life."

Make that the second greatest day of her life, because moments later Dr. Phil himself slid into the backseat and Meghan absolutely lost her mind. She started squealing and almost hyperventilating from the moment she caught a glimpse of him in the side mirror.

"I'm gonna throw up. I'm so excited," she said. Then turning to him, she added, "Your teeth look so good. He's so handsome."

With a private sessions, Meghan started talking about how much anxiety had dominated much of her life, and how she was able to channel it into her music. She also talked again about how she wound up as such a prolific songwriter, which turned out to have a genesis in the same place.

When James asked her why she thinks she went down that road than the road of being an artist herself at first, Meghan said candidly, "I think because of my looks," she said. "I looked as insecure as I felt."

The song "All About That Bass" changed everything for her as producers simply decided to let her be the artist on it. "And then all my dreams came true," she said with a smile.

A prolific songwriter for countless artists -- and she said she wants to write for everybody -- James put her on the spot to write a song right then about the traffic. And with an assist from James himself, they quickly came up with an incredibly catchy ditty.

"I'm in traffic, beep beep / I'm in traffic, beep beep! / All I'm thinking 'bout is you / And what I'm gonna do / When I get to your room / I'll give you that Zoom Zoom Zoom."

We know there's some fancy editing at play in these segments, but that was nevertheless a very impressive and very quick songwriting session to get the kernel of something with that earworm quality that can make a hit.

Elsewhere, Meghan shared just how much she adores the married life, and how she knew on the first date that Daryl Sabara was the man for her. And she has her friend Chloë Grace Moretz to thank for the whole thing.

"She set me up on like a modern-day blind date," Meghan said. "We were hanging out and I was like, Dude, I'm just trying to find a nice guy. And she was like, Well, one of my best friends is the nicest guy I know."

From there it was a double-date to the bowling alley and karaoke where Daryl serenaded her with Elton John's "Your Song." And she kew that night, "I'm gonna marry him."

James couldn't get enough of her story about their "romantic" first kiss. Especially as Chloë and her boyfriend-at-the-time, Brooklyn Beckham, kept urging them to kiss. "Brooklyn came over to me and was like, You should kiss him," Meghan laughed.

"How old were you at this point? 12?" James asked.

She even told them at the time, "You are children," insisting she would kiss him on her own time. But it wasn't much later. "I looked at my security guard, and I was like, Be gone. And that's what gave Daryl the cue, like, Oh, it's going down."

Steamy.

But everything worked out for the couple, who wed in 2018 and have been going strong since. And Daryl isn't her only fan, as it was Dr. Phil who swooped in with the plug for Meghan's new album "Treat Myself," available Friday.

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