Pippa's son Arthur, whom she shares with husband James Matthews, turned two on Thursday 15 October. The family-of-three live in a £17million home in London and given that Kate and Prince William are now back at Kensington Palace, we're sure there's been an opportunity for the Duchess to catch up with her sister Pippa.
William and Kate's youngest son Prince Louis, who also turned two in April, is expected to start nursery early next year but unfortunately, he misses out on having his cousin Arthur in the same school year.
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Pippa welcomed little Arthur Michael William Matthews on 15 October 2018 at St Mary's Hospital, having announced her pregnancy in June. She married hedge fund manager James on 20 May 2017, with her niece and nephew, Princess Charlotte and Prince George, among the bridal party.
The author, 37, documented keeping fit during her pregnancy with Arthur in her column for Waitrose Weekend magazine.
Kate with the cute bridal party at Pippa and James's wedding
Ahead of her son's first birthday last year, Pippa opened up about motherhood, writing: "Now that Arthur is 11 months old and more mobile, I have been trying to come up with different activities to do with him.
"I needed to find something more than just park walks in the pram. Our local baby gym has been a saving grace. It's a big space full of fun, soft objects, play mats, stairs, balls, swings, mini trampolines, and more to stimulate and physically engage babies and toddlers."
Kate and Pippa also have a younger brother James Middleton, who had to postpone his wedding to Alizee Thevenet this summer amid the coronavirus crisis. The couple stayed with James's parents Carole and Michael Middleton in Bucklebury, West Berkshire during lockdown.
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