When chat show host Jimmy Kimmel joked that retirement had obviously 'ruined' David, who entered the studio to frantic whooping and cheering from the audience, he was ready with a response.
"It's funny you should say that," Becks replied. "I was bathing Harper the other day... and I had got her out and was toweling her down and she said: "Daddy, I love you so much, but I don't like you - you're so chubby!"
It's no wonder Harper is image conscious, with fashion icon mum Victoria as her mentor. And David says she's already taking after her mum, who recently opened a clothing boutique on London's swish Dover Street.
"She'll come in and she'll want to put my belt on or she'll want to dress me or she'll say 'Daddy, wear these shoes with that'," he told Kimmel. "It's amazing, actually."
Another snippet of Beckham family life which emerged from the interview was that David, like most parents, spends most of his free time ferrying his brood around.
"I've become a taxi driver overnight. From seven in the morning I have four dropoffs at four different schools... Then I pick my little girl up at 12 then the boys at four. Then the boys train in a soccer academy every single night of the week until 9.30pm, so I'm busy 'til then."
However, Becks says he enjoys running around after his family after a long career which often took him away from home.
"To be honest, it's great. I've been playing football for the last 22 years, not always with the family. So it's nice to actually be at home with them."
But while David may be embracing life as a more hands-on dad, 15-year-old son Brooklyn is not as enthusiastic about having his old man hanging around.
"The young one obviously loves me taking her to school, and the two smaller boys, they love it... My eldest, Brooklyn, he says: 'Dad, park around the corner!'" David told Kimmel, revealing that he has a classic embarrassing dad technique to get his own back.
"So, I'm driving round and he's just walking in the school and I opened the window and I went: 'Brooklyn, I love you!'".
More on Parentdish: David Beckham reveals: 'Victoria and I are very strict parents'