Can't Dance, Don't Ask Me (aka Kelly's Dance) - S3-E13
Continuity mistake: During Kelly's dance, a nerdy girl grabs Bud and starts kissing him, but in the next shot, Bud is standing alone in the background. (00:20:30)
Can't Dance, Don't Ask Me (aka Kelly's Dance) - S3-E13
Continuity mistake: While Kelly is dancing with the guy at school, a nerd girl starts kissing on Bud and pushes him backwards. The very next second when the scene changes, Bud on the left side is back playing the record for the music without anyone around him.
Answer: It's implied that Steve filed for divorce since in s04e16, "You Gotta Know When to Hold 'Em", Marcy says that Steve is suing for alimony. Alimony is something that has to be requested when filing for divorce. Although the show doesn't spend time on the actual legal proceedings of their divorce.
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