It seems plausible that Sara may have been in a relationship with ED ... which is why the family had their immediate suspicions.
They may have been hiding their relationship from her family, her ex-boyfriend, his girlfriend ... maybe they had a heated argument & he murdered her - most likely in a way that didn't wake anyone up or alert anyone.
They may have been hiding their relationship from her family, her ex-boyfriend, his girlfriend ... maybe they had a heated argument & he murdered her - most likely in a way that didn't wake anyone up or alert anyone.