Every married couple knows that keeping the spark alive can be tough. Combine the stresses of modern life with work and children, and it can often feel like the romantic spark is harder and harder to ignite.
Duchess Catherine and Prince William have been married for nine years now, with three young children and very public jobs that invite a whole lot of scrutiny into their personal lives.
So it would be completely understandable if the Duke and Duchess of Cambridge were perhaps not quite so forthcoming in their public displays of affection for each other, after all these years.
But that is certainly not the case with these two lovebirds.
Kate, 37, and William, also 37, first met at university in England, at St Andrews, and became fast friends from the moment they met.
"We were friends for over a year first and it just sort of blossomed from then on," William has said of his first encounters with his now wife.
"We just spent more time with each other had a good giggle, had lots of fun and realised we shared the same interests and just had a really good time," Wills reflected.
They then dated for several years, but in 2007, the young couple actually split.
But rather than causing a permanent rift, both the Duke and Duchess say that short time apart at the beginning of their relationship actually strengthened their bond.
"I think at the time I wasn't very happy about it, but actually it made me a stronger person, you find out things about yourself that maybe you hadn't realised," Kate said during the couple's official engagement interview in 2010.
"I think you can get quite consumed by a relationship when you are younger and I really valued that time for me as well although I didn't think it at the time," the mother-of-two has confessed.
And William also agreed.
"We were both very young, it was at university, we were both finding ourselves as such and being different characters and stuff, it was very much trying to find our own way and we were growing up, it was a bit of space and a bit of things like that and it worked out for the better," the future King of England explained.
WATCH BELOW: Prince William and Duchess Catherine hold hands at Kensington Palace. Story continues after video.
Now, as Mum and Dad to Prince George, Princess Charlotte and Prince Louis, the doting parents seem to be more in love than ever, more than eight years after they famously tied the knot at Westminster Abbey in London.
While Prince Harry and Duchess Meghan are famous for always holding hands in public, the Duke and Duchess of Cambridge have always been enormously affectionate with each other - and certainly aren't shy about showing off a little bit of PDA when they're out and about.
So we've rounded up the cutest examples of their public displays of affection, proving why Prince William and Kate Middleton's love story is one for the ages.
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