Psycho Test

I got this test in the e-mail from my hubby. This is supposed to be a test used by a famous American Psychologist to check if one has the same mentality as a killer. Many arrested serial killers took part in the test and answered the question correctly. I am not sure whether it is true, but just for fun let do the test.

A woman, while at the funeral of her own mother, met a man she didn't know. She thought this guy was amazing, so much her dream guy, that she believed him to be just that! She fell in love with him right there, but never asked for his number and couldn't find him. A few days later she killed her sister.

Question: What is her motive in killing her sister?

Share your answer on the comment and check again this page tomorrow for the answer.