Model-turned-cookbook author and TV personality Chrissy reveals the open line of communication allows her to chat to the "All of Me" hitmaker whenever she attends his shows - and it doesn't affect his performances.
The microphone proved particularly handy earlier this week (begins February 17), when Chrissy urged John to publicly acknowledge the presence of their four-year-old daughter, Luna, by waving to her from the stage.
"(Luna) loves waving, and we were just at one of John's shows, actually, and I had to talk into the mic which goes directly to his ear while he's performing," the mother-of-two explained on U.S. breakfast show "Today".
"I'm like, 'Wave at Luna!' because she gets so hurt if you don't wave back to her."
Asked if the chatter disrupts John's musical focus, Chrissy insists, "It doesn't. He's very good about it. He'll say certain things in his mic back to us, like, 'I have to go pee!'"
The couple also shares son Miles, who turns two in May.