

Holy crap…you literally just unlocked that same memory for me. Idk what episode it was either, but I totally remember that part.
Edit: Found it! It’s the episode “Gary Takes a Bath” Season 2 Episode 13.
At one point, Spongebob attempts to hypnotize Gary into taking a bath, and one of the telepathic images is that weird hillbilly girl laughing.
Happy to help!