Prince William and Kate Middleton are celebrating their ninth wedding anniversary. Their relationship has always been filled with love, and not even royal traditions could keep them from showing their affection for each other.

A Beautiful Love Affair

The Duke of Cambridge is second in line to the throne next to Prince William's father, Prince Charles. With that said, Prince William and Kate have always tried to be professional, both in appearance and conduct, wherever they go.

In particular, the two always look and act regal when attending royal events.

However, little do people know that these two have their own share of PDA moments. And while they try to keep it to a minimum, there have been a handful of times when both William and Kate have shown sweet gestures to each other without restraint.

Whenever those rare yet very special moments happen, the two could not help but smile about it. Perhaps they were hoping nobody has taken notice. With all eyes on these royal figures, there is no way people would overlook their show of PDA.

With that in mind -- and as we celebrate the royal couple's love -- we compiled the top five moments Prince William and Kate were so lovey-dovey to each other.

Honeymoon Love

In a photo posted by their official photographers, both Kate and William looked young and in love as they held hands on their way to their honeymoon ride.

The two just got married then and were leaving for their honeymoon destination via a helicopter. The two appeared so happy and so in love, and they were a picture of inspiration.

New Baby, Old Love

When the couple introduced baby Louis into the world, the Duke and Duchess of Cambridge came out showing off some PDA.

Kate, who just gave birth then, looked as beautiful as always. Prince William, on the other hand, seemed like a happy father and an even prouder husband as he guided his lovely down the stairs wife while holding their newborn son.

Celebrating Love

Prince William and Kate rarely show PDA, but when they do, the royal couple looks so cute.

In another rare photo posted by E! News on their official Twitter account, the couple could be seen getting more intimate during a royal wedding celebration. Perhaps they were feeling the lovely vibe of the occassion, and it was obvious how much they love each other!

Young Sweet Love

When Kate and William celebrated during the 2012 London Olympics, people could not help but gush. After all, it's rare to see the couple EMBRACE in public.

Their love for each other was overflowing, and it was inspiring. One of the official staff members of the royal couple, Pascal le Segretain, was the one who took the photo.

Love Over The Years

The slideshow of photos of Prince William and Kate's PDA moments posted by InStyle is definitely one for the books.

The Duke and Duchess of Cambridge have always been traditional in their approach to love. But whenever they can have a few moments to truly show their affection for each other, they just do. AND THEY ARE ABSOLUTELY CUTE!

On their ninth year anniversary, Prince William and Kate Middleton continue to inspire a lot of royal fans that fairytales dp come true. In their short moments of public display of affection, they remind everyone that they, too, are humans.

They love and they are loved. They simply want to show it.

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