Oops! I didn't take this into account.

I though it might be easy for them to get Canadian VISA, since they already have the U.S. VISA (So the Canadians won't worry that they will stay in Canada forever). Besides, I live in WAshington DC. The Canadian Embassy is less than an hour's drive. I was thinking of going to the embassy tomorrow. Maybe I over-simplified the matter--true, they may get rejected. I will give it a second thought then. Thank you for reminding me.