Kat McDonough shared an apartment with her boyfriend, Seth Mazzaglia, in Dover, N.H. The two were questioned separately by police on Oct. 12, 2012.
Kat would tell police that Lizzi never came to the apartment that night, and stopped talking after about two hours.
Seth, on the other hand, spoke to police for 11 hours, and would say that Lizzi was at the apartment that night, and admitted that she died there.
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