The 55-year-old posted the adorable snap alongside a picture of himself as an adult as part of viral social media trend, "How it started, how it's going".
The never-before-seen black and white image showed the Good Morning Britain host as a very young boy sat on top of a beer keg, while the second photo showed a grown-up Piers clutching a pint of beer.
WATCH: Piers Morgan interviews his father-in-law on GMB
"How it started. How it's going," he simply wrote in the caption, which prompted several fans to comment with one writing: "Keep on going Piers, you're doing well!!" Another joked: "Certainly a good start in life!" A third post read: "I can see a resemblance of his little girl in his baby photo."
The TV presenter has somewhat had a sad childhood. His dad Vincent died when he was just 11 months old, and Glynne became his step-father when he married his mum, Gabrielle. Piers also has a brother, Jeremy, who is two years older.
Meanwhile, the outspoken broadcaster is now a dad to sons Spencer, 27, Stanley, 23, and 19-year-old Bertie from his marriage to Marion Shalloe as well as his eight-year-old daughter Elise, whom he shares with his second wife Celia.
Piers shared this rare throwback snap of himself alongside one image of him as an adult
Last year, Piers opened up about his sons as he joked that "luckily they all have their father's looks". During an interview on Loose Women, the journalist was asked whether his sons were ever embarrassed by his controversial public opinions. "Not at all," the GMB star replied. "They are perfectly entitled to disagree with me and they do often vehemently disagree with me."
As a family snap flashed up on screen, Piers teased: "They have all got their father's looks," before continuing to say: "I encourage them to speak their own minds, argue with me. But if they are going to argue with me over dinner, they better come armed as I am going to take them down. Why wouldn't you want your kids to be opinionated?"
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