The royal couple gave an interview to the BBC to highlight the "ever-increasing need" for people to take their mental health seriously during the crisis, particularly for those working on the NHS front line.
They hope that more people will talk to each other online to share their concerns and are supporting the NHS Every Mind Matters campaign.
"I think staying connected, staying positive, and being able to talk to friends and family is so crucial," William said. "And having just some tips and some ideas as to how to tackle some of these strange feelings and difficult circumstances we're finding ourselves in is really important, just to nudge us through these next few weeks."
He said NHS workers were particularly at risk: "They are there right next to the bedside looking after and caring for each and every patient who is in a critical condition.
"I think they take away that pain and sometimes that fear and that loneliness that these patients have to go through — they are the ones that absorb that and then take it home to their families."
Kate revealed what life had been like in lockdown for them: She said the couple had been homeschooling their children — George, 6, Charlotte, 4, and Louis, who turns 2 next week — and that routine was key.
"Someone gave me some very good advice, pre the [Easter] holidays, to fit some structure to keep to a pretty strict routine," Kate said. "Don't tell the children, we've actually kept it going through the holidays. I feel very mean."
She said they regularly video called family members: "It gets a bit hectic, I'm not going to lie. With a 2-year-old, you have to take the phone away. It's quite hectic for them all to say the right thing at the right time without pressing the wrong buttons. But it's great and it's nice to keep in touch with everybody."
Kate was asked whether she believed the coronavirus outbreak would fundamentally change how we value our NHS workers. "Yes, absolutely," she said.
"I think what we're seeing now is the NHS and the frontline workers are doing the most extraordinary job, and that's really come to the forefront in the last few weeks. And I think it's going to dramatically change how we all value and see our frontline workers, and I think that is one of the main positives that you can take from this.
"They do an extraordinary job, it goes unrecognised daily, and now I think all of us as a nation can really see how hard they work and how vital their work is."
William said he hoped the crisis would ultimately have a positive impact on the environment, as businesses realised they could use video conferencing rather than flying "halfway across the world just have a face-to-face for a couple of hours and come back again".
"I've always thought that was lunacy really," he said. "Why on earth we do that when we've got the technology now in place to do things? Why don't we conduct more business at home?"
MIND has an extensive list of advice, tips, and tricks on how to look after your mental health on their website, as well as where to get help and treatment if you need it. You can access that here.
YoungMinds has lots of advice about what to do if you’re feeling anxious about the coronavirus, plus advice for parents and carers on how to speak to children about it. You can access that here.
They also provide 24/7 crisis support for those who need urgent help. You can access it by texting "YM" to 85258.
Samaritans offer 24-hour confidential listening for anyone who needs it — just call 116 123.