They're both old, around a lot of people a lot, and not in the best of health. Will they get it? Who gets it worse? If one gets it and the other doesn't, does that matter? What happens if one (or both) dies?
It's called the Presidential line of succession. That's why it's important to also consider who the VP is going to be.
Good questions......... but a perhaps somewhat more relevant question for both of them might be will the CORONA virus set the stage for a global economic reset that may begin in Canada and / or in Australia? COVID 19 and unconditional income supplement to all Australians https://www.facebook.com/SeanFraserMP/posts/2637804269833837