By Alexandra Whittaker
May 18, 2018 @ 11:15 am

Turning 13 is often considered a milestone birthday, marking the moment when a kid becomes a teenager. For many, it's a birthday full of sweet surprises and mementos.

And, if you're Prince William, it also consists of birthday cake shaped like boobs, courtesy of mom.

Princess Diana poked a fun at her eldest on his 13th birthday by playing into his infatuation with supermodels, as former royal chef Darren McGrady explained to InStyle. 

Tim Graham

"He was really into Cindy Crawford and he put a poster on his wall. Princess Diana invited three supermodels, [including] Christy Turlington, to come over and have tea with them. And when I opened my refrigerator door in the kitchen, she had actually ordered a cake with a huge pair of naked boobs, and that was just to embarrass William," McGrady said.

"So the butler took the cake in. They all sang happy birthday, William turned bright red, and Harry said, 'Wow! Can I have that cake for my birthday?' So Harry was always the fun one. Harry was always the mischievous one."

McGrady—who is partnering with Kellogg's on a royal wedding breakfast—worked as Queen Elizabeth's chef for 11 years before moving to Kensington Palace with Diana and the kids for 4 more years until Diana's death in 1997. After spending so much time with them, it's safe to say McGrady knew the family well, and he saw firsthand how much the princes took after both Diana and Prince Charles. 

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"Looking at the two of them, William is sort of very reserved and very deep like his father, and Harry's the party one, the fun one, and he reminds me so much of the princess," McGrady said. "Not just the fun side, but the way he is with children, the way he just finds it easy to be around children, and the way he reacts to all of the charity work, the incredible work that he's done for the Invictus Games and things."

While he won't be in London for the ceremony, McGrady will be busy preparing a multicourse meal at the Kellogg's New York City Café for American royal fans beginning at 5:30 a.m., because what's a royal wedding without a royal-approved meal?