Complex sentence: The clown can be eradicated by boosting the moods and overall morale of any Sims residing in the household and selling any "Tragic Clown" paintings in the household will prevent his return.
Split into simpler sentences: The clown can be eradicated by boosting the moods and overall morale of any Sims residing in the household. And selling any "Tragic Clown" paintings in the household will prevent his return.