The unidentified man and the 51-year-old Forest Hills mom reportedly had an affair, and he knew where the family kept their spare key, the outlet said citing sources.
Gaal's home, where she lived with her 13- and 17-year-old sons and husband, Howard Klein, had reportedly not been broken into. The crime appeared to have been fueled by anger, and was unplanned, sources in law enforcement told the outlet.
Gaal's body was found by two walkers in the area after a blood trail led to her home, around 8 a.m., Saturday, April 16. She had been stabbed some 58 times in the neck, torso, and left arm. The sources also revealed she had wounds to her hands in an attempt to fight off her attacker.
In a chilling twist to the story, Gaal's husband, Howard Klein, reported receiving a text from her phone after the crime saying the killing was revenge for her sending him to jail years ago and "your whole family is next," the Daily Mail reported.
Gaal's tragic death has sparked several theories surrounding her mysterious death, many being discussed on a Facebook forum devoted to cracking the case.
Gaal had last seen on Friday night when she told her 13-year-old son Leo she was going out with friends.
After the discovery of his mother's body, Leo was handcuffed and questioned by NYPD before being released later Saturday. Gaal's husband and older son were out of town on a college visit at the time of the crime.
Investigators believe that Gaal was attacked in her basement, while the 13-year-old son was on the top floor of the home.
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