McGavin played The Old Man in one of my favorite movies, A Christmas Story, as well as the part of Carl Kolchak on the mid-1970s TV series Night Stalker, and in a bunch of other roles.
Knotts was, in my opinion, one of the funniest people God ever put on earth. He had as much to do with the success of The Andy Griffith Show as Andy himself, and he was in rare form in the film version of No Time For Sergeants, as the corporal in charge of testing dexterity. He was a regular with Steve Allen and had his own show for a while, which no one seems to remember.
Anyway, I'll miss them both. God bless, guys. You done good.