The couple released a video to mark their son’s first birthday featuring footage of Meghan reading Archie the book Duck! Rabbit! by Amy Krouse Rosenthal. And during the clip, which was shot by Prince Harry, Meghan can be heard calling Archie “Arch”.
She says: “Let’s go to the next page, look Arch!”
Harry posted the video on the Save With Stories Instagram account, a campaign from the charity Save the Children, which provides support for disadvantaged youngsters.
Experts said the cute nickname was appropriate for the royal baby as the Greek word “Arche” means “source of action”.
This is believed to have been the inspiration behind Archie’s name and also the name of the Sussexes’ forthcoming charity initiative, Archewell.
In the video, Meghan reads the story to her inquisitive son, who grabs at the pages and at one point appears on the verge of tears before breaking into a smile.
In the footage his mother gives him a kiss on the cheek and lovingly calls him “Arch” as Harry can be heard making approving noises in the background.
In a funny moment, the one-year-old reaches for something out of sight and picks up a book, and the duchess says “let’s finish this book first, then we’ll have that book”.
But he then drops it on the floor and when Meghan tucks it down the side of the chair out of sight he reaches for it again and makes his father laugh by throwing it to the ground.
At the end of the story Meghan cuddles her son and says “good job”, while Harry, still behind the camera, whoops and says “bravo”.
A caption with the video said: “‘Duck! Rabbit!’ with Meghan, The Duchess of Sussex (and Harry, The Duke of Sussex behind the camera), read to their son Archie for his 1st birthday. Happy Birthday, Archie!”
The royal baby sports a full head of hair and is wearing a t-shirt and a nappy in the video, which is thought to have been recorded in the US, where Meghan and Harry are observing the COVID-19 lockdown.
The couple have made their home in Los Angeles where they and other residents of California have been living under a “stay-at-home” order made by the state’s governor, Gavin Newsom.
They plan to bring up their son in the US and split their time with the UK after walking away from the Royal Family in order to become financially independent, after their hopes of earning money while still supporting the Queen were ruled out.
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Archie has experienced an eventful 12 months since he was born at London’s Portland Hospital on May 6 2019 at 5.26am, weighing 7lb 3oz.
His first home was Frogmore cottage in the grounds of Windsor Castle, then an exclusive property on Vancouver Island in Canada, and he now lives with his parents in the sprawling metropolis known as the City of Angels.
Meghan and Harry have previously called Archie by another sweet nickname.
During their tour of South Africa last autumn Meghan was heard calling her only child “Bubba”.
In video footage of Archie meeting with Archbishop Desmond Tutu, the Duchess says: “Say hello, hello. Oh Bubba!”
Nicknames have a long tradition throughout the history of the British monarchy and the House of Windsor is no different.
Prince Philip reportedly calls the Queen “cabbage” and the Sussexes are known to call each other Meg and H.