Steve Granitz/FilmMagic; Axelle/Bauer-Griffin/FilmMagic Mila Kunis; Reese Witherspoon and Ashton Kutcher
"She goes, 'You guys look so awkward on the red carpet together,'" Witherspoon, 46, told Hoda Kotb and Jenna Bush Hager on Monday's Today show, adding that Kunis, 39, said so via an email to her and her husband the night before.
With Witherspoon a petite 5-foot-1 and Kutcher, who turns 45 on Tuesday, checking in at well over six feet, the leads have been having fun over the past week at various events while publicizing the Netflix film — even if they don't exactly see eye to eye.
At a photo call for the movie last week at the Four Seasons Hotel in Los Angeles, Kutcher goofily crouched down to Witherspoon's vantage point, while in other red carpet snaps, the duo have displayed body language that plays up their differences in height.
In real life, the actresses have been longtime friends, so Kunis's comments were happily received by the Legally Blonde alum — as was the entire experience she had while working with Kutcher.
Noam Galai/Getty Images for Netflix
"It's just fun 'cause when you know a girlfriend so much, it was just fun to get to know her significant other 'cause I've loved her for so long," Witherspoon said on Today.
Giving constructive criticism is seemingly a Kunis trademark.
In a recent cover interview with Esquire, Kutcher recalled how Kunis — whom he famously costarred with on That '70s Show and eventually married — told him " 'You were an a------,' after they started dating, referencing how he acted following his split from Demi Moore.
" 'Was I?' " the actor recalled asking Kunis.
" 'Yeah, you were an a------ for a good two years,' " she said at the time, according to Kutcher.
Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.
Now, the actor couldn't be more grateful for Kunis, whom he said "is so much cooler than" him.
"The thing about Mila that made our relationship accelerate was that I had always admired her," Kutcher said. "Her talents, her skills, her gifts. But I knew that she didn't need me. And she knew that I didn't need her."
Your Place or Mine is streaming Feb. 10 on Netflix.