That is, the pair were comparing their daughter's "poop faces" on Monday's "Jimmy Kimmel Live!"
"That's my favorite thing about babies, is they all have these different poop faces," Tatum confessed.
The actor then proceeded to demonstrate his one-and-half-year-old daughter Everly's "poop face."
"I can't help but think that it reminds me of Marlon Brando in 'The Godfather' when he dies," he said with a laugh. "Every time!"
Tatum also demonstrated his own stoic reaction to Everly's poop face, explaining, "You're not supposed to react...because you don't want to distract them."
Kimmel joked, "She's probably telling her friends, 'My dad has the weirdest face he makes when I poop.'"
The host then shared his six-month-old daughter Jane's "poop face" -- ending with a growl.
"It's almost animalistic," Kimmel said. "There's a growl that goes along with it."
Check out the proud papas in the video below.