Despite the trend that the Duke and Duchess's name choice has already started across the UK, the Downton Abbey scriptwriters were gave the name to Lady Mary's son, who is Downton's heir, before the royal couple.
The traditional moniker was apparently chosen as a tribute to King George V, under whose reign the hit period drama has been set, when filming for the fourth series began back in February.
Michelle Dockery as Lady Mary Crawley and baby George and Allen Leech as Tom Branson with Sybil
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Season four of the hit ITV show is set in 1922, which is six to eight months after Lady Mary Crawley, who is played by Michelle Dockery, gave birth to baby George during the show's Christmas special.
Viewers' joy then turned to shock, however when fate dealt Mary a tragic hand at the end of the episode when her husband, Matthew Crawley, was killed in a road accident.
New images released by ITV show a widowed Mary with young George standing next to Tom Branson whose partner, Lady Sybil, also died in the last series. In tribute to his late wife Branson, who is played by Allen Leech, named his daughter Sybil as well.
Downton Abbey's fourth season will hit UK screens in September and is already expected to pull in millions of viewers.
Julian Fellowes, who created the show, says the fourth season will see a change in pace and the drama will be slow and more subtle that previous series in order to focus more on character development.
Widower Tom Branson and his daughter Sybil
As well as baby George and young Sybil, nine new characters will join the Downton cast while Dan Stevens, who played Matthew Crawley, and Siobhan Finnerman, who played Lady Grantham's maid, Sarah O'Brien, will be notably absent.
New cast members include welsh actor Tom Cullen who takes on the role of Lord Gillingham, a potential suitor for the widowed Lady Mary and an old Crawley family friend who has known Mary since childhood. Foyle's War star Julian Ovenden, 36, is set to play the aristocratic Charles Blake and Former Eastender Nigel Harman also joins the show as a visiting valet named Green.
Maori soprano Dame Kiri Te Kanawa is also set to feature in the show while fellow Dame Harriet Walter will star as Lady Shackleton, a friend of Dame Maggie Smith's character, the Dowager Countess.
Daisy Lewis, Gary Carr and Joanna David have also joined the Emmy-award-winning series.