The Good Morning Britain host paid tribute to NHS staff for "fighting as hard as Derek is to give us the chance to be reunited".
Sharing a video of her son Billy playing a drum during Thursday's clap for carers, Ms Garraway wrote: "Hear this might be the last clap for carers so Billy thought we should get the drums out to go out in style!
"Its been such a source of weekly comfort for them & me & I must admit I felt the tears come tonight to think it’s coming to an end while our fear for Derek goes on.
"But even if we don’t clap next Thursday it won’t diminish my eternal thanks to all in the NHS."
She added: "They are keeping Derek alive & everyone of them is fighting as hard as Derek is to give us the chance to be reunited. Hope has to keep us all going doesn’t it?"
Ms Garraway said she was having to find new ways of staying strong for her two children, Billy and Darcey, as "I know Derek would want me to".
"It’s not easy but when I think of how hard Derek is fighting & the bravery of all in the NHS it helps."
Fellow Good Morning Britain host Susanna Reid commented on her post, saying: "So much love" with a loveheart emoji.
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