Kate Middleton
Pregnant Kate Middleton helped with the drill during the Tennis for Kids session in her recent visit to Lawn Tennis Association. Pictured: Middleton visits The Sunken Garden at Kensington Palace on Aug. 30, 2017 in London. Getty Images/Chris Jackson

Kate Middleton played tennis on Halloween.

Middleton, 35, opted to celebrate Halloween by playing her favorite sport. The Duchess of Cambridge visited the Lawn Tennis Association and even joined the Tennis for Kids session, where she showed off her athletic skills, People reported.

Middleton arrived solo at the center in the morning dressed in a designer tracksuit. The royal mom sported black Monreal track pants worth €250 ($332), black Clarice track jacket and white Nike Air VaporMax trainers that cost around €193 ($256), Express reported.

Upon arrival, the Duchess was greeted by the leaders before she headed to the court. She then met tennis pro Johanna Konta and the group of children who joined the kids' tennis session. According to Konta, the kids were very excited to meet a princess.

"It was good and fun. She's lovely," Konta said of Middleton. "It was great to see her passion for tennis and that she was here to learn about these great programs being run by the LTA. Every little girl and almost every boy wants to meet a princess and it got them very excited."

In this clip shared by Simon Perry on Twitter, Middleton helped train the kids with the drills. "Princess of Tennis! Helping kids with drills @BritishTennis national centre," Perry wrote in the caption.

Middleton is a self-confessed tennis fan. In fact, before she married Prince William, she used to spend hours lining up just to get tickets for Wimbledon. For the royal, seeing the tournament in person is important to her.

"Being able to go into Wimbledon and be part of an amazing atmosphere is special," Middleton said. "It inspires young people including myself. Every time Wimbledon is on I am thinking 'Yes, I could do the same' and get out the racket. Sadly, not the same results."

Meanwhile, aside from playing tennis, a royal expert said that Middleton and Prince William may celebrate Halloween privately with Carole Middleton and Pippa Middleton. While the royals do not usually celebrate the holiday, the Duke and Duchess of Cambridge may enforce their own practice with their kids.

"The royals certainly don't publicly celebrate Halloween, however, Kate's mother, Carole Middleton and sister, Pippa Middleton might well put their party planning skills to good use," Christina Reeves said. "It's likely they will throw a private party for George and Charlotte behind closed doors. Whether it's rustling up a quick pumpkin pie or soup, I'm sure they won't let it go unnoticed."

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