Georgia Tennant is a doting mother to five children, with her youngest, Birdie, being born in March 2020.
MORE: David Tennant and wife Georgia treat son to unbelievable Zelda themed cake
Alongside Birdie, Georgia is also mum to Ty, 19, Olive, ten, Wilfred, eight and Doris, six.
While enjoying the bank holiday weekend, the mum-of-five shared an adorable picture of Birdie enjoying the sunshine in a multicoloured dress.
WATCH: Georgia Tennant melts hearts with adorable video of Birdie dancing
"#freeasabird," the doting mum captioned her post, adding an emoji of sunshine.
Fans were left shocked at how much the little girl had grown, as one said: "Wow, she's grown up so much. So nice to see such a happy little girl."
Another added: "She's SO big, omg," and a third asked: "Wait, what happened, where's the infant?? Where's Birdie?? This is a whole grown child."
A fourth jubilant fan posted: "Oh wow she's so big! She's adorable and so happy!"
The actress shares her five children with her husband David Tennant, who adopted Ty in 2012, following his marriage to Georgia.
Fans couldn't believe how much Birdie had grown
The couple recently marked a romantic milestone as they celebrated their 13th year together, the pair will celebrate their tenth wedding anniversary in December.
MORE: David Tennant and wife Georgia treat daughter to unbelievable aquatic cake
MORE: David Tennant seen in very rare photo with daughter Birdie at storytime
The star marked the event by sharing a selfie with her husband, with a hilarious caption. "13 years of slightly [explicit] selfies made passable with a filter," she joked.
Fans were quick to comment on the cute tribute, with one writing: "Happy thirteen years to my two favourite celebrities."
Another remarked: "Love you both, thank you for inspiring me as a child. Happy Anniversary."
David, 50, and Georgia, 36, quietly tied the knot on 30 December 2011, before celebrating with a star-studded New Year's Eve reception at London's Globe Theatre.
The couple met in 2008 when they were both filming for Doctor Who.
Georgia shares her five children with husband David
Georgia recently opened up about life at home during lockdown with David and their children, and joked to the Radio Times: "It was the worst. It brought out the worst in us as parents. There was one point in something like week two, where I went, 'I'm sorry. I just have to…' and I climbed out the window and sat on our roof.
"It was the only place I could go where I knew that no one would think to look for me, because, 'Why would Mummy be sat on the roof?'"
The doting wife continued: "At that point we had no idea how long it was going to last for. And the idea that this could be until the children were 18… I thought, 'I can't do this. I've had so many kids – no one told me there was gonna be a pandemic.'"
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