Derek contracted coronavirus last year and spent over a year in hospital, before he was finally discharged and able to return home in April 2021.
WATCH: Kate Garraway breaks down in tears after NTAs win
Sadly, his battle is ongoing as he suffered several complications including brain inflammation and damage to the lungs, kidneys, heart and liver, and now requires round-the-clock care and is "rarely communicative".
"Suddenly, without warning, Kate said: 'He's next to me now. Why don't you ask him yourself?'" he wrote. "I was stunned. The last time I spoke to Derek was nearly two years ago at my Christmas pub party in December 2019."
Kate's husband Derek spent one year in hospital
He continued: "'Derek!' I cried. 'It's so good to talk to you!' There was a slight pause and then I heard a familiar male voice say very clearly and strongly: 'Hello!' I was stunned, again.
"'HELLO!' I stammered back. 'It's great to hear your voice again. Keep battling, Derek – we’re all so proud of you!' There was another pause, then I heard him say the words 'Thank you' - again, very clearly."
Last month, Piers revealed that he is quitting Life Stories after 12 years and that his good friend and former GMB colleague Kate would taking over.
"I'm quitting Life Stories after 12 years and 100 shows," he tweeted. "My final one will be with my fabulous friend @kategarraway and she will then present the remaining 3 planned shows of the next series as I leave ITV to host my new global daily show. It's been a blast!"
Life Stories began in 2009 and has seen Piers interview the likes of Sharon Osbourne, Mo Farah, Simon Cowell, Cheryl and then-Prime Minister Gordon Brown.
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