Kate Middleton and Pippa's sisterly bond in photos

Pippa Middleton was by her older sister Kate Middleton's side for the Duchess of Cambridge's 2011 royal wedding to Prince William. While Kate won't be reciprocating as maid-of-honor at Pippa's May 20, 2017 nuptials, she will of course be there for her sibling every step of the way. Discussing her relationship with Kate in a 2014 NBC interview, Pippa admitted, “We have a very normal sisterly relationship. We’re very close and we support each other and get each other’s opinions.”

Click through for a look at the sisters' close bond over the years.

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The Middleton sisters, pictured with their father Michael, moved to Amman, Jordan for two and a half years when they were younger before moving back to England. The girls are a part of a close-knit family that includes younger brother James Middleton, who was born in 1987.

Photo: The Middleton Family

Before their own respective weddings, Kate and Pippa were twinning as bridesmaids at their uncle's 1991 nuptials. As young girls, the sisters helped out in the family business and reveled in country walks and cozy Christmas celebrations during which their father would amuse them by wearing costumes. One year the Middleton patriarch made an entrance as a sumo wrestler.

Photo: The Middleton Family

The stylish duo stepped out for a London book launch party in 2007. The sisters have been inseparable since they were young and attended the same boarding school Marlborough College together. There, they both played on the hockey team, where Pippa had the added distinction of being captain.

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Kate and her younger sister had a fun night out on the town in London back in 2008. The sisters smiled for the cameras as they sat in their car.

Photo: Mark Milan/FilmMagic

Pippa had no problem third-wheeling with Kate and Prince William at a March 2006 field game at Eton College. While her sister has married into the royal family, the youngest Middleton daughter previously revealed to the Today show in 2014 that they treat each other normally. Pippa said, "I think that's really the heart for all of us is having a really close family that we can sort of be normal with each other, treat each other normally. And that's sort of kept us all, you know, affixed to the ground."

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Carole and Michael Middleton's daughters showed off their style credentials stepping out for a 2011 wedding at St. Michael and All Angels church in Lambourn, England.

Photo: Indigo/Getty Images

In 2006, Kate and Pippa did some sister bonding on the sidelines as they watched Prince William compete in a polo match. Since becoming a Duchess, Kate has remained close to her sister and family. They have even continued their trips to Mustique with the Middletons.

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Kate and Pippa, who both enjoy watching tennis, attended the 2012 Wimbledon Championships together. The duo have spent many matches together and with their significant others in the stands.

Photo: LEON NEAL/AFP/Getty Images

The Middleton girls’ charm has much to do with the example of their supremely calm and collected, elegant mother Carole, who never seems fazed by her daughter Kate’s royal in-laws. Together she, Kate and Pippa make a formidable trio who stay right up to date on each other’s lives, and love to exchange clothes and make-up tips.

Photo: Getty Images