Pippa Middleton Is Pregnant, Expecting Baby No. 3 With James Matthews: Reports

Surprise! Pippa Middleton is pregnant again, just over a year after welcoming her second child, according to reports.

Kate Middleton's younger sister, 38, is expecting her third baby with husband James Matthews, People magazine reported on June 5, citing multiple sources. The two are already parents to son Arthur, 3, and 14-month-old daughter Grace.

Page Six first reported about Pippa's pregnancy on June 4 after the author, wearing a smocked green dress, made a rare public appearance at the Platinum Party in the Park concert outside Buckingham Palace in London that evening. The outlet quoted a source as saying that Pippa and her husband are "so happy" and that she is a "natural mama."

E! News has reached out to Pippa's rep for comment.

At the concert, one of several event celebrating Queen Elizabeth II's Platinum Jubilee, Pippa was joined by Matthews, 46, her brother James Middleton, 35, and his wife Alizée Thévenet, and parents Carole Middleton and Michael Middleton.

Pippa Middleton's Pregnancy Style

Seated separately in a royal box, Kate, 40, attended the event with husband Prince William, 39, and kids Prince George, 8, and Princess Charlotte, 7, the eldest of their three children. The couple's youngest son, Prince Louis, 4, did not join them.

Pippa rose to fame in 2011 when millions of spectators worldwide watched her serve as Kate's maid of honor at the duchess' royal wedding to William. Pippa married Matthews in 2017 and George and Charlotte served as a page boy and flower girl, respectively.

Kate's sister, who is notoriously private, last summer gave a rare interview about keeping fit while parenting in association with sportswear label Hoka One. "Being active with my 2.5-year-old son in the park or playground, transporting him on the back of my bike and buggy running when he was a baby have been ways in which I have been able to include outdoor exercise whilst being a hands-on mummy," she said, per Hello! magazine.

"Being such an active family has rubbed off on my son," she continued. "He loves nothing more than running wild in the woods, parks and fields with our two dogs, even if it's howling a gale and pouring with rain."

Pippa also said in the interview that her "dream would be to participate in a sporting challenge or epic adventure with my own children, like I was lucky enough to experience as a child."

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