Continuity mistake: When Kelly is at the grill, right after being called a "dullard" by Bud, Kelly grabs Bud's wrist with her left hand. As we pan out on the exact same scene, her hand is nowhere near his wrist.
Factual error: Al uses ashes to cook food on the grill. You can't just throw ashes in a grill and light them! They wouldn't light at all. That's like trying to light cigarette ashes and expecting them to burn hot enough to cook food.
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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