In Season Five, Louis Chirillo has been replaced with Trevor Devall. And it is EXTREMELY noticeable, with the entire voice pitch changed and Trevor struggling to keep the same inflections with obvious throat pain (going by the rough, scratchy noises). And for all his effort he just ends up sounding like Hugh Test.
Mary Test was voiced by Brittney Wilson in Season One, Ashleigh Ball in Season Two-Four, and back to Brittney Wilson in Season Five after Ashleigh Ball left the show to voice Rainbow Dash and Applejack.
Toilet Humor: "Dookie" was a juvenille euphemism for poop in the 1970s.