Continuity mistake: At the start of the church ceremony, Junior and Roberta are present, so it must be a weekend because they would have to be at school on a weekday. Later that same day when Cleveland is washing a mule he says it's Wednesday when it should be a Saturday or Sunday. (00:10:50 - 00:12:20)
Continuity mistake: When Cleveland and Donna notice Rallo has disappeared out the window, the window changes size between shots. (00:14:20)
Continuity mistake: The tree the scuba diver is impaled on changes size between shots when everyone runs out of the courthouse. (00:14:40)
Continuity mistake: Junior's inflatable scout pants go over the waterfall twice when he saves Rallo. (00:19:35)
Answer: In the episode "A Rodent Like This" Rallo discovers that Cleveland Jr. is actually a secret agent who is tracking down Tim, who is actually criminal. Jr. reveals that in order to get close he had to eliminate the real Cleveland Jr. luckily Cleveland doesn't pay attention so it was easy. Whether or not this is canon or not depends on the writers.