Prince William and Kate Middleton shared a sweet moment in their recent engagement.

On Tuesday, the Duke and Duchess of Cambridge stepped out again after reuniting with the other members of the royal family for another joint engagement. They visited the Troubadour White City Theatre in London.

Just when the couple was about to leave and making their way to their car, Middleton accidentally stumbled. Prince William immediately reached out to his wife as she recovered her balance. The duchess seemed not bothered at all as she giggled with her husband.

Aside from this, many noticed how affectionate they were on the same outing. According to Cosmopolitan, they shared “ultra-rare PDA” moment when Prince William touched Middleton’s back because they rarely show intimacy in public, so it was a big deal.

Prince William and Middleton are set to be the next king and queen consort after Prince Charles. Unlike Prince Harry and Meghan Markle who often hold each other’s hand in public, the Duke and Duchess of Cambridge are not very tactile and follow the example of Queen Elizabeth II and Prince Philip, who also rarely pack on the PDA.

Although Prince William and Middleton rarely hold hands while walking especially when they are attending public engagements, the couple has a signature sign of affection and that’s giving each other a subtle touch. Many also noticed that they look at each other with love and affection.

A snap of Prince William and Middleton was shared on Twitter. In the picture, the couple is looking at each other in the eye and royal fans couldn’t help but react.

Many said that they could sense the pair’s passion, love and respect for one another. Others noted that they are a “perfect couple” and “soul mates.”

“College sweethearts! I love their love story, the part that the prince  fell in love with a commoner and the Queen is supportive, his family is supportive;it’s a matter of Catherine accepting the royal life and is handling it well & with three kids now. I love their happy ending,” one fan commented on Prince William and Middleton’s romance.

Kate Middleton and Prince William Prince William and Kate Middleton attend the 1st Battalion Irish Guards St Patrick's Day Parade at Cavalry Barracks on March 17, 2019 in Hounslow, England. Photo: Getty Images/Gareth Fuller