The couple's son Wilfred marked his ninth birthday and in honour of the occasion, Georgia shared a snapshot of his incredible cake along with a loving tribute.
WATCH: Georgia Tennant's daughter makes her movie debut
She wrote: "Happy 9th Birthday Wilfred! Funniest, kindest and most unique person I know. Glad you came out of me (even with the stitches) #happybirthday @cakesbyrobincakes."
The cake in question was themed around Pirates of the Caribbean, showing Johnny Depp's Captain Jack Sparrow sitting beside a treasure chest and holding a bottle of rum. Monster's tentacles can also be seen surrounding a pirate ship, emerging from carefully-sculpted waves.
Fans were in awe of the incredible design and rushed to the comments section to compliment the cake and wish Wilfred a happy birthday.
However, a number also noted the 'topical' theme in light on the ongoing trial between Johnny and his ex-wife, Amber Heard. "Team Johnny," one simply wrote, while a second said: "Very apt cake!!"
David, 50, and Georgia, 37, have been married since 2011 and together share five children, including 19-year-old Ty, whom David adopted.
David and Georgia – whose dad, Peter Davison, was the fifth actor to portray the famous Time Lord between 1981 and 1984 – met when she starred alongside him in the Doctor Who episode, The Doctor's Daughter, in 2008.
Around the World in 80 Days actor David usually keeps his private life behind closed doors, but once opened up about his marriage to Georgia when a Guardian journalist jokily suggested he'd deliberately picked a partner who was the daughter of a Doctor. "That's exactly what I did, yes!" he replied. "And there were very few candidates available. It was a limited field."
Like this story? Sign up to our HELLO! Mail newsletter to get other stories like this delivered straight to your inbox.