During a visit to Leicester on Wednesday, Kate Middleton let a little family secret slip. People reports that the duchess told someone what Prince George calls his dad. While the rest of the world calls him Prince William, Duke of Cambridge, KG, KT, ADC, Prince George has a slightly shorter name: “Pops.”

Kate and William were in the city to attend a ceremony celebrating the life of Vichai Srivaddhanaprabha, chairman of the city’s soccer team. After paying their respects, the two mingled with the crowd and when one of the other attendees asked Middleton about her children, she let William’s nickname slip.

Prince William and George

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Fiona Sturgess, a soccer fan and royal devotee, revealed that “Kate said that William was playing football with the children last night and one of them said, I think it was George, ‘Are you playing football tomorrow, Pops?'”

It’s not George’s only nickname. In The Queen at Ninety, a BBC documentary that gave viewers a behind-the-crown look at the royal family, Kate added that the little prince has a nickname for his grandmother, too. She also gave fans a little bit of info on just how much the queen loves her grandkids.

“George is only 2-and-a-half and he calls her ‘Gan-Gan,'” Kate said. “She always leaves a little gift or something in their room when we go and stay, and that just shows her love for her family.”