In 2006, Stewart and Charles were photographed chatting happily at a Buckingham Palace garden party for the charity.
Aside from their charitable endeavors, the king has also bonded with Stewart over their health struggles.
“[Charles] had treatment today, he told me.

I went through all that.
I had treatment five days a week.
Like him, I was still working.

He’s remarkable,” Stewart enthused at the time, per theDaily Mail.