He has rarely been glimpsed since his parents stepped down as senior members of Britain's royal family.
But Meghan, Duchess of Sussex, has shared a new glimpse of Archie Harrison Mountbatten-Windsor to mark the tot's first birthday.
To celebrate Archie's big day, which falls on Wednesday, May 6, the former actress took part in a fundraising video in which she reads to her son.
The footage, posted on Save the Children's Instagram page, shows the duchess treating Archie to a rendition of Duck! Rabbit!, a children's book by Amy Krouse Rosenthal and Tom Lichtenheld.
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The picture-based book is centred on an optical illusion: are the images showing a sweet little duck or a cute rabbit?
The toddler can be seen smiling, laughing and helping turn the pages in the three-minute video.
The clip was filmed by Prince Harry, Duke of Sussex, for the non-profit organisation's Save with Stories initiative.
The movement calls for donations to help vulnerable families affected by the coronavirus pandemic, with funds raised going towards providing early learning packs, supermarket vouchers, essential household items and virus protection.
Actor Nicholas Hoult, magician Dynamo, Dame Helen Mirren and Jude Law are among the famous faces who have also read children's books for videos to help raise funds.
The Duke and Duchess of Sussex, who moved to Los Angeles last month, have not released any other statement to mark their son's birthday.
Kensington Palace, the account that represents the Duke and Duchess of Cambridge, earlier shared a photo from Archie's christening.
"Wishing Archie a very happy first birthday today!" the caption read.
Clarence House, which represents Prince Charles and Camilla, Duchess of Cornwall, shared a photo taken from the same day.
"A very Happy Birthday to Archie, who turns one today," the caption added. "This photo of Archie and his grandfather was taken following his christening in July 2019."
The Royal Family account, which represents Queen Elizabeth II, shared an image that was taken when the monarch met the newborn Archie.
"Happy Birthday to Archie Mountbatten-Windsor who is celebrating his first birthday today!" the caption stated. "Archie is the Queen’s eighth great-grandchild."