kate middleton
OCTOBER 18: Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge attend the Coach Core graduation ceremony for more than 150 Coach Core apprentices at The London Stadium on October 18, 2017 in London, England. Getty

As the mother of two little ones and pregnant with another, you'd think Kate Middleton had mastered the art of Halloween preparations.

But the Duchess of Cambridge will be spending the holiday in a less than frightful way, instead enjoying a spot of tennis during a visit to the Lawn Tennis Association.

Kate, 35, may be expected to turn up in a pumpkin-inspired orange outfit since she is such a fan of literal dressing, as the event takes place on 31 October.

The sporty engagement will feature a wheelchair tennis demonstration while Kate will take part in the Tennis for Kids session, an LTA-run programme which teaches young children aged five to eight on how to play and enjoy tennis.

Prince Harry and Meghan Markle
Prince Harry is set to spend Halloween in Toronto with Meghan Markle Getty

The royal will also get the opportunity to meet and chat with some of the country's top junior talents, along with other members of the training team including coaches, nutritionists and physical therapists.

Tennis fan Kate may pay particular interest to advice for budding tennis players since she previously revealed that son Prince George, four, was keen on the sport.

Former British number one Greg Rusedski chatted to the duchess at 2016 Wimbledon and told reporters: "She talked about George, her little boy, playing tennis. He's got a racket and he enjoys playing tennis, and obviously she plays with William. So they obviously enjoy the sport very much."

Offering advice on Prince George's prospects as a future tennis champion, Rusedski said: "As long as he is enjoying it at this age that's all that matters, really. It's too young to know what's going to happen for the future, but it's one of those sports for life."

Kate, who is expecting her third child in April with husband Prince William, became patron of the LTA in December 2016, taking over the patronage from Queen Elizabeth who held the role for 63 years.

Tennis has always been a sport close to Kate's heart, claiming that it was part of her upbringing. She said: "It is such a quintessential part of English summer. I was really taken by Agassi and Sampras, Ivanisevic and Steffi Graf. That for me was my first memories."

The duchess isn't the only member of the royal family with alternative Halloween plans, as Prince Harry is jetting to Toronto, Canada, to spend quality time with his Suits actress girlfriend of 18 months Meghan Markle.