Since then, we saw plenty of the little heir to Downton growing up on the show while hanging out with his cousins, Sybbie and Marigold.
In reality, George is played by brothers Oliver and Zac, who are triplets with their sister, Megan.
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Proud mum Clare often posts snaps of what they have been up to on social media, and opened up about homeschooling the trio during the COVID-19 lockdown, writing: "Happy June! It's back to homeschooling for this lot today after a week off enjoying being nine - only a few months until double digits)!
They've had sleepovers in each other's bedrooms, camp outs in the garden & generally playing nicely (most of the time - there have definitely been arguments)."
She also shared a sweet pair of the triplets with crazy hair during lockdown, jokily writing: "LockDown hair! As well as having a HUGE growth spurt over the last few months, Zac, Megan & Oliver's hair has gone wild and I'm loving it!"
Sybbie Branson - Fifi Hart
Fifi has played Tom and Sybil's daughter Sybbie from a young age - but she looked so grown up during the Downton Abbey premiere!
Hugh Bonneville shared a snap posing with Fifi and her big sister, affectionately calling himself the Downton children's nickname for him, 'Donk'.
He wrote: "Donk and Sybbie...’ ...aka Fifi Hart... and with her equally glam big sis... #shesincrediblytall #oh #shesstandingonachair."
Twins Eva and Karina play Edith's daughter Marigold, and Hugh Bonneville shared a snap of them on the set of the Downton Abbey film.
He captioned the post: "It's Grandpa time at Donk’s crèche… with Eva & Karina Samms who play Marigold, Fifi Hart and Zac and Oliver Barker (George)."
While not much is known about the actor who plays Anna and Bates' son, little Johnny Bates was welcomed in the final season of Downton Abbey, and an adorable never-before-seen picture of the Bates' family - with Johnny now a toddler - was released ahead of the highly-anticipated movie's release back in 2019.
The Facebook picture was posted in honour of Mother's Day, with the caption reading: "They do say a mother's love is the strongest love there is. – Anna Bates. Happy #MothersDay. #DowntonAbbeyFilm."