Here is a painting of my great grandfather "Happy". I'm pretty sure he fought with the Canadian armed forces in WWI, being that he was born and raised in Nova Scotia. Can anyone identify what his uniform might indicate? I was told he did corpse removal in the trenches.

And here is a picture of his son, my grandfather, Winston, who fought in WWII. He was also born and raised in Canada but became a US citizen at some point during the war. I've been told conflicting stories that he fought for Canada or that he fought for the US despite being underage and not a US citizen. Can you see any identifying features on his uniform that might prove one way or the other?

I'm fairly certain my brother has ironed out all the details already, but I figured this would be a more fun way to find the facts myself. Any info would be great! Thanks!