Believe it or not, even Kate Middleton gets teased sometimes. In the upcoming ITV documentary Our Queen at Ninety, the Duchess of Cambridge revealed why the royal family makes fun of her.

"There's a real art to walkabouts, everybody teases me in the family that I spend far too long chatting," Middleton, 34, explained of her one flaw as an over-friendly queen-in-training. "I still have to learn a little bit more, and to pick up a few more tips, I suppose."

Luckily for the mom of two — who wasn’t born into royalty — her in-law Queen Elizabeth II has been there to help prepare her for her future as a sovereign.

"She's been generous and not forceful at all in her views,” reflected Middleton, who married Prince William in 2011. "And she's really been there in a gentle guidance for me."

Despite carving out time to show the duchess the royal ropes, the 89-year-old Queen has been dutifully doting on her two adorable great-grandkids, George, 2, and Charlotte, 10 months — especially her little princess.

“The queen, she was really thrilled that it was a little girl. And I think as soon as we came back here to Kensington, she was one of our first visitors,” Middleton noted. “I think she’s very fond of Charlotte, always watching what she’s up to.”

While she has a soft spot for Charlotte, Elizabeth also shares a special bond with big brother, George. And, as Middleton pointed out, the toddler even has a sweet nickname for the current ruler of the British Monarchy.

“George is only 2 1/2 and he calls her ‘Gan-Gan,’” the proud duchess gushed. “She always leaves a little gift or something in their room when we go and stay, and that just shows her love for the family.”

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