Appearing on That Gaby Roslin Podcast, the mum-of-five confessed the period David was also out filming ITV's chilling drama Des was "not a good time" for them as a family.
"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."
WATCH: Georgia Tennant unveils daughter Birdie's new talent
"It was a bit of a vortex, shooting that," explained David, to which Georgia added: "It wasn't like you came home and had the kids throwing themselves around your neck, was it?"
"I got a phone call during the first night of the shoot, which was a night shoot," the doting dad continued. "I suddenly saw I had so many missed calls from Georgia... I found myself in hospital."
Georgia and David share five children together
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.'
At the time, Georgia shared this photo of her baby girl in hospital
"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."
Of their other children dealing with the news, 49-year-old David shared: "I think the other kids were a bit traumatised by it… but I think we only noticed that months later." He added: "We were very lucky, this was an illness that passed and she completely recovered from it."
The couple have been married since 2011
Georgia, 35, confessed that it has been hard to let go of those memories during that difficult period. "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," revealed the actress. "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."
The couple are also loving parents to four other children; 18-year-old son Ty, nine-year-old Olive, seven-year-old Wilfred and five-year-old Doris. David adopted Georgia's son Ty from a previous relationship when they married.
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