Drew Peterson, a former police officer, had been married many times and was known to cheat on his wives, and then marry his mistress. His third wife, Kathleen Savio, was found dead in her bathtub after he divorced her. It was ruled an accident, and then later his fourth wife, Stacy Peterson, went missing. Police were suspicious and ended up exhuming Kathleen from her grave to reevaluate her cause of death, which then opened up the legal investigations into Drew's involvement.
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