Prince Harry and Meghan Markle share never-before-seen photo from Archie's Christening

The Duke and Duchess of Sussex have released a new picture from their son Archie's Christening to celebrate Prince Charles' 71st birthday.

The Prince of Wales - Prince Harry and Prince William's father - celebrated his birthday on Thursday (14.11.19), and the royal couple sent their "pa" and Archie's "grandpa" a special message as they released the black and white snap taken by their photographer Chris Allerton to mark the special occasion.

Alongside the sweet portrait posted on the official Sussex Royal Instagram page, they wrote: "Happy birthday to His Royal Highness The Prince of Wales - Sir, Pa, Grandpa! (sic)"

Charles - who spent his birthday in Mumbai, India - can be seen glancing lovingly at his grandson in the family picture, as Harry, 35, cradled his newborn in his Baptism gown.

Harry and Meghan's son - whose full name is Archie Harrison Mountbatten-Windsor - was christened in a private ceremony at Windsor Castle in July.

At the time, the couple announced: "This morning, The Duke and Duchess of Sussex's son, Archie Harrison Mountbatten-Windsor was christened in the Private Chapel at Windsor Castle at an intimate service officiated by the Archbishop of Canterbury, Justin Welby. The Duke and Duchess of Sussex are so happy to share the joy of this day with members of the public who have been incredibly supportive since the birth of their son. They thank you for your kindness in welcoming their firstborn and celebrating this special moment. Their Royal Highnesses feel fortunate to have enjoyed this day with family and the godparents of Archie."

Archie was baptised wearing a handmade replica of the royal christening gown, with the original being used as early as 1841.

The statement continued: "Their son, Archie, was baptised wearing the handmade replica of the royal christening gown which has been worn by royal infants for the last 11 years. The original Royal Christening Robe, made of fine Honiton lace lined with white satin, was commissioned by Queen Victoria in 1841 and first worn by her eldest daughter.

"It was subsequently worn for generations of Royal christenings, including The Queen, her children and her grandchildren until 2004, when The Queen commissioned this handmade replica, in order for the fragile historic outfit to be preserved, and for the tradition to continue."

The Duke and Duchess of Sussex were joined by Archie's grandfather and his wife, the Duchess of Cornwall, Harry's brother and his wife, the Duchess of Cambridge, Duchess Meghan's mother Doria Ragland and Harry's late mother Princess Diana's sisters, Lady Sarah McCorquodale and Baroness Jane Fellowes, at the ceremony.

- Bang! Showbiz