Royal PDA Dos and Don'ts: How Affectionate Can Royal Couples Be in Public?

In addition to their titles as the Duke and Duchess of Sussex, Prince Harry and Meghan Markle were also widely viewed to be the holders of another unofficial title: most affectionate royal couple! However, Harry's cousin Zara and her husband Mike Tindall have proved that they are also not afraid of a little PDA.

While walking around the fairgrounds at the Festival of British Eventing at Gatcombe Park on in August 2018, Zara and Mike were seen sharing a sweet kiss on the lips as Queen Elizabeth's granddaughter cheekily held onto her husband's backside.

Mike was later seen returning the affectionate gesture as the pair — who welcomed their youngest daughter, Lena Elizabeth, last year — continued to stroll around the event.

Their PDA continued just days later when the parents couldn't stop smiling and keeping each other close at the Isle of Wight's annual Cowes Week Regatta.

Royal etiquette expert Myka Meier, founder and director of Beaumont Etiquette, tells PEOPLE that there are no formal rules on royal couples being lovey-dovey in public — it's at their own discretion.

"Senior members of the royal family would likely not be told how to interact or when they can or can not show PDA and would be trusted to use their better judgement as to when it's appropriate," she explains. "The royals often adjust PDA to mirror the formality of the event they are attending. At a somber or more formal event, we are less likely to see PDA than at a casual event where it would be deemed more fitting."

She adds, "It's also important to note that when attending official events on behalf of the royal family, royals are taking on professional roles, versus being on their own private time, which the recent photos of Mike and Zara Tindall not on official royal duty would be an example of."

Even at official royal events, couples may adjust their displays of affection depending on "the formality of the event, their duties, the culture and the mood of the environment. They are trusted to make their own judgment calls on what is appropriate in the situation they are in. For example, at a somber event such as Remembrance Day, you are less likely to see affection among royal couples than at an event deemed entertaining (think Royal Ascot).

As soon as Prince Harry and Meghan went public with their romance, it was clear that they were not afraid to show PDA. Those displays of affection continued when Meghan became an official royal at their wedding in May 2018.

"They are not afraid to hold hands. They don't mind showing their emotions," veteran royal photographer, Mark Stewart, told PEOPLE.

Since they made their very first appearance together at the Invictus Games in Sept. 2017, the royal couple has held hands, rubbed each other's backs and linked arms in public — they even snuck their signature move into Prince Louis' official christening portraits and shared a kiss on the lips at Harry's charity polo match.

The couple's closeness was on display during Meghan's very first royal outing with her then-fiancé during a Dec. 2018 visit to Nottingham. They walked around holding hands and with their arms around each other as they greeted enthusiastic fans in the town center.

"While Prince Harry and Meghan holding hands is atypical for royal engagements, it is a seemingly welcomed gesture to show unity and celebration of their engagement period," Meier told PEOPLE at the time. "There is no protocol that says they can not show affection on official engagements, and this gesture makes them relatable and lovable to the public."

She continued, "Meghan and Prince Harry holding hands at a royal engagement is a refreshingly modern approach to their new role both as a couple and as representatives of the royal family."

Harry and Meghan's open affection is indeed a departure from usual royal behavior. A certain decorum tends to be the norm when it comes to official royal outings. Prince William and Kate Middleton, for example, rarely show PDA.

"It is rare to see royal couples holding hands on official outings," Meier shared. "While we are much less likely to see The Duke and Duchess holding hands in public, we often see Prince Charles and The Duchess of Cornwall holding hands — it's all simply a matter of preference for each couple and is also likely dependent on the nature of the event they are attending. A more serious engagement would warrant a more serious level of professionalism, which each royal is sure to follow."

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Queen Elizabeth and Prince Philip did not show affection in public either. Despite their closeness (over 70 years of royal marriage!), they are never seen holding hands in public due to the "stoic values" of their generation, royal biographer Gyles Brandreth told PEOPLE.

Harry and Meghan followed suit, respectfully refraining from holding hands around the prince's grandmother.

Meier also points out that there are some lessons that regular couples can take away from their favorite royals.

"1. PDA such as a hand on the back or hand-holding shows care and comfort and is a safe bet," she says. "2. When in a professional role, practice professional behavior. 3. If you ever are engaging in PDA that may make someone uncomfortable, it's best to take it to private quarters. An occasional sweet Sussex peck is one thing; a salacious snog is another!"