While Prince Harry and Meghan Markle are known for being more private than other royals, it does not mean that their in-laws -- Prince William and Kate Middleton -- wouldn’t grab the chance to be more inconspicuous when they can. In fact, the Duchess of Cambridge, recently, managed to attend an event without alerting the general public by using one very simple trick used by most celebrities.

According to Express, Kate was able to catch up with other school moms at a pub in Chelsea without attracting too much attention to herself. To pull off the sneaky move, the Duchess used a secret entrance to the establishment.

The low-key event was a get together with other moms whose children Thomas’s school in Battersea just like Prince William and Kate Middleton’s two older children Prince George and Princess Charlotte. Thanks to the back entrance of the Hollywood Arms, the duchess was able to attend the “meet and greet” drinks party virtually unnoticed save for other school moms.

The get-together is an annual event held for parents of new students at Thomas's Battersea. This year, Kate Middleton was attending for the four-year-old Charlotte, who started attending the school in September.

The event was held at the Hollywood Arms' Boulevard Bar, which can hold up to 80 persons. The venue reportedly costs £2,500 for one night.

The doorway was located in a back alley as an option for people who want to go in and out of the establishment without going through the main entrance. This feature is especially helpful for those who are avoiding photographers.

However, Kate Middleton is not the only royal to have used the secret entrance to the pub. In fact, it was specifically made for a particular member of the family during his party-going days.

According to the Daily Mail, the backdoor entrance was purposely installed for Prince Harry when he was still a bachelor. Prince Charles and Princess Diana’s younger son was known as a party-lover with a care-free lifestyle in his younger years and was even involved in a few minor controversies, such as that time when he was once photographed naked while partying in Las Vegas.

Kate Middleton Catherine, Duchess Of Cambridge, visits The Foundling Museum on March 19, 2019, in London, England, to understand how they use art to make a positive contribution to society by engaging with vulnerable and marginalised young people. Samir Hussein/Samir Hussein/WireImage