The royal wedding will be a special day not only for Prince Harry and Meghan Markle, but also the loved ones who will be joining the celebrations in Windsor. And someone who is sure to be very proud is the Duchess of Cambridge, who has a strong relationship with the groom, having known him for close to 15 years.
Prince Harry and Kate have always had a close bond
Since she started dating Prince William at St Andrew's University in 2003, Kate has also forged a close bond with his family - in particular Prince Harry, who she appears to have taken under her wing and considers as a younger brother alongside her siblings Pippa and James Middleton. The pair always look to be having fun when they attend royal engagements together, with Harry often making Kate burst into hysterics with his down-to-earth humour.
See Prince Harry and Kate's sweetest moments together
In turn, Kate has offered guidance and support to Prince Harry at the times when he has struggled with life in the public eye. She appears to have been fundamental in helping to welcome Meghan into the family too, with the former Suits star saying the Duchess had been "wonderful" at sharing advice and making her feel settled into her new role as a royal.
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The royal wedding is sure to provide even more special moments from the duo, but for now, take a look back at some of Prince Harry and Kate's sweetest sibling moments from the past few years.