Holly Willoughby and Phillip Schofield have one of the tightest bonds in telly, and it turns out they're so close they're able to communicate in a secret language.
The This Morning hosts revealed how they try to wind each other up when they've found something funny that they shouldn't.
But viewers watching at home have no idea that they're doing it.
Speaking at the This Morning Live event last year, Phil, 57, said he elbows Holly, 38, in the side when he wants to make her laugh.
He explained: "I know if Holly is on the brink; we have the same sense of humour it works at the same speed.
"I know if something is making me laugh inside I know it's also making her laugh inside."
He also admitted to staring at her just to put her off even more.
Holly said: "I know he's looking at me and it's really annoying."
"The more intensely I look, the more I think 'She's gonna go,'" Phil added.
"A guest will say something and, you won't see this, just between us we're doing that."
And Holly said it was Phil's distinctive laugh that really pushes her over the edge.
She revealed: "He's got that laugh, like Muttley the dog where he gets all wheezy.
"The moment he starts wheezing next to me it's game over."
*This Morning airs weekdays at 10:30am on ITV
