Kate Middleton is going to be an aunt again: Her sister Pippa Middleton is expecting her third child, according to reports. A source told Page Six Pippa and her husband James Matthews are "so happy" and Pippa is a "natural mamma."

She debuted her baby bump at the Party at the Palace concert on the third evening of Queen Elizabeth's Platinum Jubilee weekend. Pippa and James attended with Pippa's brother, James Middleton, and James's wife Alizée Thévenet.

queen elizabeth ii platinum jubilee 2022 platinum party at the palace
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Kate's siblings attended the Platinum Jubilee concert with their spouses,
queen elizabeth ii platinum jubilee 2022 platinum party at the palace
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Pippa glowed in a green dress.

Pippa and James married in May 2017, and they have two children already: Arthur Michael William Matthews, 3, and Grace Elizabeth Jane Matthews, 14 months. Pippa gave birth to Arthur and Grace in the Lindo Wing of St. Mary's Hospital—where Kate welcomed her three children, Prince George, Princess Charlotte and Prince Louis.

wedding of pippa middleton and james matthews
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Pippa Middleton and James Matthews leave church following their wedding ceremony at St Mark’s Church, May 20, 2017.

James is a hedge fund manager, the chief executive of Eden Rock Capital Management Group, and a former professional racing driver. His father is Laird of Glen Affric, an estate in Scotland; James and Pippa will inherit the Laird and Lady titles, though may not use them—and their children will have no aristocratic titles.

Pippa's newest baby will be the sixth grandchild for Carole and Michael Middleton. "I want to run down the hills, climb the trees and go through the tunnel at the playground," Carole told Good Housekeeping UK about being with her grandchildren. "As long as I am able to, that’s what I’ll be doing. I cook with them, I muck around dancing, we go on bike rides.”

From: Town & Country US
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Emily Burack
Senior News Editor

Emily Burack (she/her) is the Senior News Editor for Town & Country, where she covers entertainment, culture, the royals, and a range of other subjects. Before joining T&C, she was the deputy managing editor at Hey Alma, a Jewish culture site. Follow her @emburack on Twitter and Instagram.