Prince Harry continues: "We feel stressed, low, anxious or have trouble sleeping".
"This for me is a subject and a conversation that's not talked about enough".
"It's like looking in the mirror", the prince then hilariously jokes, letting viewers get a glimpse of the pair's outfits. He then goes on to meet Harry and discuss the issues common to both of them: having ginger-coloured hair.
He said: "That's what I'm trying to do, people just don't understand what it's like for people like us - with the jokes and the snide comments". "Though we have continued to put on a courageous face - as so many of you can relate to - I cannot begin to describe how painful it has been. Maybe there's been a slight miscommunication but this is actually about World Mental Health Day".
Despite its amusing start, the video ends on a serious note as the Duke of Sussex asks viewers to try and look out for those who "may suffer in silence".
The video ends with Harry and Sheeran encouraging people to seek help if they're struggling with mental health.
Hilariously, the camera then pans to Ed deleting the words "Gingers Reunite" from his Powerpoint presentation.
In the post's caption, the Duke and Duchess reminded followers that "we are all in this together".
Harry and the Duchess of Sussex's official Instagram account trailed the collaboration by posting a video of the duke welcoming in the star and a film crew. "We're all in this together", Prince Harry said.
More than a million fans viewed the exchange within an hour of it being uploaded on social media on Wednesday.