‘IF’ hits theaters May 17

Ryan Reynolds and Blake Lively‘s kids had not seen their dad’s latest movie IF before the film’s premiere on Monday, May 13, but they did watch the trailer and were hooked.

“They’ve seen the trailer, and they don’t stop watching the trailer,” Reynolds, 47, tells PEOPLE on the red carpet at the SVA Theater in New York City.

Reynolds and Lively’s children watched the trailer so much that it became “a little tricky” in the morning, Reynolds says. He would have to remind them, “We’re going to school right now. We’re not watching the trailer. We’re going to school,” he says.

The children “love the trailers” for IF and were “excited” to finally see the film, the actor says.

“They love the trailers, and then they watch all those little thirty-second spots that you can YouTube. They’re pretty obsessed with it,” Reynolds tells PEOPLE.

Reynolds also jokes that they “worship” their dad’s costar, Cailey Fleming, his top choice to babysit them among the IF cast.

Lively, 36, and Reynolds are parents to daughters Ines, 7½, James, 9, and Betty, 4½. They also welcomed a fourth child, whose name has not been publicly revealed, in February 2023.

Related: Emily & John! An Office Reunion! See All the Big Stars at the IF Premiere in N.Y.C.

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IF writer-director John Krasinski was joined by wife Emily Blunt and their costars Reynolds, Steve Carell, Maya Rudolph, Bradley Cooper, Matt Damon, Awkwafina, Amy Schumer, Bobby Moynihan, Christopher Meloni, Fleming and more on the red carpet Monday.

IF is about a girl (played by Fleming) who has superpowers that give her the ability to “see everyone’s imaginary friends” and uses her gift to “reconnect forgotten IFs with their kids,” according to a synopsis.

The movie’s first trailer opened with Reynolds tiptoeing across a kid’s bedroom toward a closet door as the words, “What if everything you believed as a kid was real?” flashed across the screen.

The closet opened to reveal a large, furry, purple imaginary friend (voiced by Carell) who stepped out and says hi before unleashing a massive sneeze.

She went on to ask, “What is happening?” prompting Carell’s character to explain, “I’m an IF, get it? Imaginary friend.”

IF effectively reunites Carell and Krasinski, who starred together on the hit NBC sitcom The Office from 2005 until Carell’s exit in 2011.

While appearing on the Today show Monday, Reynolds chatted about whether his kids with wife Lively (who also voices a character in IF) have imaginary friends of their own.

“My daughter Betty, she has a very vivid imagination, so there’s always somebody standing behind me and I turn around quickly like a horror movie and I realize no, it’s just Harvey from the old movie Harvey. It’s a 6-foot-5 rabbit,” said the father of four.

“At least it’s not Deadpool. That would be … that’s NSFK. Not safe for kids,” teased co-host Savannah Guthrie.

“No, I ruined them with that because I have the original suit … like a mold of my body downstairs in the basement,” said Reynolds as Guthrie joked she was “starting to understand those issues you’re talking about.”

“Yeah, exactly. And it was just sort of silhouetted one night and one of my kids went down there, screamed bloody murder,” Reynolds recalled. “I ran down there because I forgot it was down there and I screamed bloody murder. So yeah, no, everybody’s pretty well damaged.”

IF is in theaters Friday, May 17.

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