Royals Pippa Middleton and James Middleton Attend Wimbledon One Week After Sister Kate's Appearance Pippa took some fashion inspiration from her older sister, wearing a similar outfit to Kate's ensemble for Archie's royal christening over the weekend By Stephanie Petit Stephanie Petit Stephanie Petit is a Royals Writer and Reporter at PEOPLE. People Editorial Guidelines Published on July 8, 2019 10:58 AM Share Tweet Pin Email Kate Middleton isn’t the only tennis fan in the family! The Duchess of Cambridge’s siblings, younger sister Pippa Middleton and younger brother James Middleton, joined up for a siblings’ day out at Wimbledon on Monday. Pippa, who welcomed her son Arthur in October 2018, was pretty in pink, sporting an ensemble by Stella McCartney. Perhaps the new mom took a little fashion inspiration from her older sister — Kate wore a pink dress by the designer on Saturday for nephew Archie‘s royal christening. Pippa, 35, accessorized her look with a matching wide-brimmed Panama “Rocks” hat by Luisa Kelsey. However, she removed the headtopper as she and James took their seats in the royal box to watch Serena Williams, Novak Djokovic and Roger Federer on Centre Court. Turns out, that’s because wearing a hat from the royal box is discouraged. “Protocol – dress is smart, suits/jacket and tie, etc. Ladies are asked not to wear hats, as they tend to obscure the vision of those seated behind them,” according to Wimbledon’s description of the royal box on their website. James, 32, looked sharp in a grey suit paired with a light blue shirt and navy tie. Both siblings wore sunglasses as they took in the tennis tournament. Pippa and James Middleton. Neil Mockford/GC Images Pippa Middleton. Karwai Tang/Getty Kate Middleton Says Prince George Has Played Tennis with His Favorite Player, Roger Federer! Just like Kate, Pippa and James (as well as their parents!) have been staples at Wimbledon over the years. Back in 2012, Pippa and Kate even attended the tournament together. And the Middletons don’t just watch the sport — they’re all avid players as well. Pippa even said she continued to swim, play tennis and keep up with her barre workouts during her pregnancy. James Middleton and Pippa Middleton. Clive Brunskill/Getty I The outing comes nearly one week after Kate surprised royal fans by making a Wimbledon appearance — but rather than take her normal seat in the royal box, she headed over to Court 14 to watch British player Harriet Dart play American Christina McHale. The royal mom of three — who sported a white shirt dress with buttons down the front accessorized with an Alexander McQueen belt, chic sunglasses and her signature blowout — later headed to Centre Court where she then took her iconic seat in the front row of the royal box to see Tatjana Maria play Angelique Kerber. Kate Middleton. Karwai Tang/Getty Can’t get enough of PEOPLE’s Royals coverage? Sign up for our newsletter to get the latest updates on Kate Middleton, Meghan Markle and more! Kate Middleton. Karwai Tang/Getty “It is such a quintessential part of English summer,” Kate said of the tennis tournament in 2017. “I was really taken by Agassi and Sampras, Ivanisevic and Steffi Graf. That for me was my first memories.” Kate is also patron of the All England Lawn Tennis and Croquet Club, which hosts the world’s most prestigious annual tennis champion.