Kate, 39, spoke to five nurses from University Hospitals Coventry and Warwickshire NHS Trust (UHCW), on a video call and heard how staff have held dying patients' hands, comforted grieving families and even played patients' favourite songs.
The Duchess, wearing a white shirt and blazer, spoke to the medical workers from Sandringham, the Queen's Norfolk residence, close to Prince William and Kate's country abode Anmer Hall, where their three children are currently being homeschooled.
Kate told them during Tuesday's video call: "You hear time and time again about the amazing things nurses up and down the country are doing, going that extra mile."
WATCH: Duchess Kate thanks nurses for going the 'extra mile'
She continued: "And it's the things that, you know, it's not part of the training and the things that you're taught but the things that come from your heart.
"And I think that's what matters so much now, these acts of kindness to the patients you're looking after, that are in your care, that family members aren't able to be there, but you are going that extra mile and being there."
It was a nurse from UHCW who delivered the first COVID vaccination in the world to 91-year-old grandmother Margaret Keenan in December at University Hospital in Coventry.
Since then, more than 440,000 vaccines have been delivered across the Midlands with the vaccination programme continuing in the region.
Kate spoke with nurses from UHCW
Kate hailed the vital role that nurses are playing in the vaccine rollout and spoke with Caroline Rudd and Judith Smith, two retired nurses who first met when they began their training in the late 1970s and have returned to the NHS to help with the vaccination programme in care homes.
The Duchess also heard a touching story from senior nurse Vasu Lingappa, who held the hand of a dying patient and played his favourite band Bon Jovi after his wife could not make it to his bedside.
Mr Lingappa, a critical care outreach practitioner, told Kate: "A lot of people are dying and we normally have families surrounding them during the last hour, but we're not able to do that.
Kate at the launch of the Nursing Now campaign in 2018
"And if I can give you a little example, we had a gentleman and unfortunately he was dying, so we spoke to his wife and she said, 'I can't come to see (him) but can you make sure you sing Bon Jovi and hold his hand?'.
"And I said, 'if I sing Bon Jovi in my accent. It won't be appropriate'. So I took my phone out and played a YouTube video of Bon Jovi and I held his hand."
He went on to say: "It's been tough, but like I said earlier, I’m surrounded by some amazing people with lots of skills and inspirational stories.
"We are nurses (some) working in critical care for 30 years, 35 years, 40 years – so there is nothing they haven't seen, but this is unprecedented."
The Duchess and the Countess of Wessex marked International Nurses' Day last May
Nursing Now works with partners around the world to advocate for more nurses in leadership positions and help them access better education and training, while also supporting them to share research and evidence of effective practice.
It's a campaign close to her heart as the Duchess' great-grandmother and grandmother were both volunteer nurses.
Kate's video call with the group of nurses comes after Prince William revealed his pride at his grandparents, the Queen and the Duke of Edinburgh, receiving their COVID-19 vaccinations, as he paid tribute to frontline workers administering the injections across the UK last week.
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