D.W.'s Very Bad Mood is the second part of the eighteenth episode of Arthur season 2. D.W.'s Very Bad Mood aired on April 27, 1998. It aired with the episode "Arthur vs. the Very Mean Crossing Guard".
D.W. has been very upset and angry for several days straight. Francine and Arthur spy on D.W. and they discover that she is upset over not being invited to a classmate's birthday party. That was after D.W. gets punished.