Marking one year since that fateful day, the 35-year-old – who shares five children with husband David Tennant – shared a snapshot with her little girl and a picture of a hospital bed as she described the terrifying period as her "darkest days".
Georgia thanked the NHS staff at Chelsea and Westminster Hospital, writing: "One year on from the darkest of days. Thanks to @nhsenglandldn for giving me the chance to smile like this and also be furious at how much blonder she is than me. #nhs @chelwestft."
WATCH: Georgia Tennant unveils daughter Birdie's new talent
Fans and friends rushed to post heartwarming messages, with one saying: "So glad she's here, healthy, well, and much blonder than you." Another remarked: "Hurrah for the kiddo and hurrah for you!"
Just last month, Georgia and her husband David opened up about the difficult time they went through during a candid chat on That Gaby Roslin Podcast.
Reflecting on that period, during which David was filming ITV's Des, Georgia said: "Our baby was very ill at that point, he would be bringing [work] back to the hospital, where I would be sat staring at our baby for hours on end. So I wasn't really aware what he was doing during that role."
The actress posted this snap with her little girl
The couple, who have been married since 2011, welcomed their daughter Birdie in October last year. After she fell ill, their little girl was kept in hospital for a week.
"At the beginning we were a bit like, 'She's fine, it's like a bit of a cold, it's not a problem', and then within 24 hours of that it was, 'No we're not fine. It's a bit more serious,'" revealed Georgia. "Within three days we got into intensive care and then it was, 'Oh man, this is really not what I thought I was signing up for here.'
Georgia and David share five children together
"But because our NHS is amazing, they saved her and we got to go home again," she added. "But then even when we got to go home, I remember the doctor saying, 'You think this is the hard bit, but the hard bit is when you go home because people go, the baby's fine, they move on, and... there was a period of time when we didn't think we were going to have her anymore and that lasts for a really long time."
Georgia then admitted that it has been hard to let go of those memories during that difficult time. "Our baby still shares our bed because I'm sure I still make that happen... It's me wanting to make sure that her breathing is fine and that everything is going to be ok," the actress shared. "We don't get any sleep but that's ok, I haven't had any sleep for about 18 years now, I'm used to it."
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