EXCLUSIVE: Ashton Kutcher Reveals His 'Secret Passion for Singing,' Says He Wants Blake Shelton on 'The Ranch'

Kutcher lent a helping hand to Thomas Rhett during a performance over the weekend, which might have been enough to give the actor the singing bug.

Ashton Kutcher lent a helping hand to Thomas Rhett during a performance over the weekend, which might have been enough to give the actor the singing bug.

Kutcher, 38, sang the third verse of Garth Brooks' "Friends In Low Places" alongside Rhett, 26, at the Back Porch Revival show in Iowa on Saturday. The event benefitted the Native Fund, a nonprofit co-founded by Kutcher and former NFL player Dallas Clark, meant to assist Iowans in need.

"I have a secret passion for singing," Kutcher told ET's Sophie Schillaci, "although I've been relegated to an absolute understanding that I'm not world class."

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While he might not be picking up GRAMMY wins anytime soon, Kutcher is winning brownie points with his 1-year-old daughter, Wyatt. Kutcher told us that he sometimes puts her to sleep with lullabies.

"I sing what I need to sing," he said. "'Wheels on the bus go round and round, round and round, round and round.' I've got that one down."

Rhett on the other hand is one of country music's biggest up-and-comers.

"I'm a 'Beer With Jesus' guy," Kutcher told ET, sharing his favorite Rhett songs. "I think that might be one of the greatest licks in country music ever ... I think he's such an honest song writer. I think he actually just truly writes what he feels and thinks, and I admire him for that."

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Kutcher and Rhett weren't the only ones to take the stage at Iowa City's Kinnick Stadium for the event. Blake Shelton gave a headlining performance, which girlfriend Gwen Stefani watched via Periscope from her concert in California.

The Ranch actor had never met Shelton before Saturday's show, but the two could get to know each other well if Kutcher has anything to say about it.

"I'd have him on [The Ranch] in a second," Kutcher said. "I'll tell him that tonight."

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The Netflix sitcom, which debuted earlier this year, was renewed for a second season. Check out the video below to see the mini That '70s Show reunion that happened at the show's screening.

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