Most recently, the ABC journalist made sure to show his support for his good friend following a milestone moment on her talk show, Live.
After sharing BTS clips on social media from the first day on set with Mark, David penned: "Most beautiful of full circles. Congratulations."
The full circle referenced the fact that Kelly and Mark first met on the set of All My Children in 1995. They went on to welcome three children - with their daughter Lola, 21, joining them on their first day in the audience of the show.
Another full circle moment for the pair as parents occurred during the show too, as among the guests for the first episode was "psychic intuitive medium" Char Margolis.
During the program, the psychic got to meet Lola two decades later from her appearance in the show in November 2000, when Kelly was not yet a co-host of Live, but was serving as a guest co-host.
During the episode, Char accurately predicted on live television that the TV host was pregnant with Lola, before the now mom-of-three had told anyone. By then Kelly and Mark had already welcomed three years earlier their eldest son, Michael, now 25.
Lola is an aspiring musician – last year she released her debut single, Paranoia Silverlining – and their little brother, Joaquin, 20, is a wrestler for Michigan University.
David has a close bond with not only Kelly, but her entire family.
The 20/20 journalist regularly appears on Live as a guest and the pair previously opened up about their friendship.
During an episode in November 2022, Kelly told the World News Tonight host: "I kind of miss our weekends together," at which point David mentioned that they'd often spend days by the pool and barbecue together and did so at the start of summer. She even revealed that her kids loved having David over, especially when it came to barbecues and other fun summer activities.
"You are a great grill master, your cheeseburgers are delicious," Kelly gushed. "Joaquin would rather eat at David's than anywhere else on earth," which left David surging with pride and happiness.
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