The post, captioned with a simple red heart emoji, shows Barnett’s head poking out from behind a bush-covered wall and lit archway.
Pixie, 30, is seen standing in the archway behind a sheer cloth, her backlit silhouette displaying a burgeoning baby bump.
The announcement comes four years after she married the These New Puritans drummer in June 2017.
Messages of congratulations for the couple have poured in from friends, with model Daisy Lowe calling Pixie a “magic mumma”, while Project Zero, an environmental charity, commented, “Such a great shot! Sending love Pixie & George”.
Pixie, the third daughter of Bob and the late television presenter Paula Yates, began modelling in 2008 when she appeared on the cover of Tatler magazine.
Since then, she has featured in advertising campaigns for a range of fashion brands, including Levi’s, Diesel, Vivienne Westwood, Loewe and lingerie maker Agent Provocateur.
Aside from modelling, Pixie also advocates against animal testing in the cosmetics industry and marine wildlife conservation, telling Elle in 2016 that sharks are her “spirit animal”.
She is one of the ambassadors for the #PassOnPlastic campaign against the pollution of water by single-use plastic, led by Project Zero and Sky Ocean Rescue.
In 2018, she was among a crowd of people who marched on the United Nations in New York to present a petition launched by The Body Shop to end cosmetic animal testing worldwide.
The petition reached more than 8.3 million signatures, however testing on animals is still legal in many countries across the world including China and most of the US.
Paula died from a heroin overdose at her home in Notting Hill on Pixie’s 10th birthday. In 2014, Pixie’s elder sister, Peaches, was found dead at her home in Kent. An inquest found that she had died from opioid intoxication.
In an interview with The Guardian in 2016, Pixie said her sister had made “such an impact” during her life.
“Things stop for a second with people like her. She changed worlds, both when she was alive and when she wasn’t,” the model said.
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