The Duke of Sussex attended Lady Gabriella Windsor’s wedding to Thomas Kingston on Saturday.
Harry arrived at St George’s Chapel – where he married his wife Meghan last year – alongside Sophie Winkleman.
The royal, who became a dad on May 6, looked dapper in a black tuxedo and pinstriped trousers.
Read more: Meghan gave birth to baby Archie at London’s Portland Hospital
Harry was accompanied by his uncle and aunt, the Earl of Wessex and the Princess Royal, who was joined by her second husband Vice Admiral Timothy Laurence.
Meanwhile, Harry’s grandmother the Queen was joined by Prince Philip as the Duke of Edinburgh made a rare public appearance two years after his retirement.
Pippa Middleton and her husband James Matthews were also in attendance.
Lady Gabriella and her new husband Thomas kissed on the steps of St George’s Chapel following the ceremony, and posed for photos.
It’s believed Harry’s wife Meghan stayed at home looking after their baby son Archie Harrison.
Meghan welcomed her baby boy with her husband Prince Harry in the early hours of May 6.
The couple had hoped for a home birth at Frogmore Cottage on the Windsor Estate, however, it was said Meghan was taken to hospital on Sunday night.
It was confirmed on Friday that Meghan gave birth to Archie at London’s Portland Hospital.
Read more: New dad Harry leaving wife Meghan and son Archie at home again for another overseas trip
Last week, Meghan and Harry proudly showed off their son to the world for the first time in front of cameras inside St George’s Hall at Windsor Castle.
Speaking about parenthood, new mum Meghan – who looked radiant in a white blazer dress – said: “It’s magical, pretty amazing. I mean I have the best two guys in the world. I’m really happy.”
Harry continued: “It’s great. Parenting is amazing. It’s only been two days, three days, but we’re just so thrilled to have our very own bundle of joy.”
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