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Read this question, and post your answer. This is not a trick question. It is as it reads. No one I know has gotten it right - including me:

A woman, while at the funeral of her own mother, met this guy whom she did not know. She thought this guy was amazing, She believed him to be her dream and she fell in love with him right there but did not ask for his number and no matter how hard she tried she could not find him. A few days later she killed her sister.

Question: What is her motive in killing her sister? Give this some thought before you answer. I'll post the answer after some people have had the chance to guess.