The household I'm curently playing has triplets that are now teens. Unfortunately, when they get the mood swing, many of their wishes are to fight, insult or snub each other. The three went out to egg a house, but one was caught by the neighbor and the police and was grounded. She snuck out to the movies and got into even more trouble. Same one also skipped school one day.
@NancyJ: Like Figwit said, it is a glitch. Look to see if your sim still has the grounded or similar moodlet and see if you can cancel it out with testingcheats. You may also want to check if your sim can do the ask for forgiveness interaction with the parent still.