By Jericka Duncan

PHILADELPHIA (CBS) – “I know what Jason did is a horrible, horrible, thing,” said 59-year-old Kathleen McGrath, of Danboro, as she showed pictures from when she says she dated Sharon Smith; the mother of accused killer, Jason Smith.

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She is breaking her silence.

“My heart goes out to his family cause I know the type of person his mother was,” McGrath continued.

Police charged 36-year-old Jason Smith with the murder of Dr. Melissa Ketunuti.

Eyewitness News obtained exclusive video of Ketunuti walking to her Graduate Hospital home.

Smith, an exterminator who had an appointment with Ketunti, follows behind moments later.

When investigators brought Smith in for questioning, police say he admitted to the brutal slaying; telling authorities that Ketunuti disrespected him.

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Police say he strangled Ketunuti and would later set her body on fire.

“He had an infatuation with fire; lighting matches, setting small fires, stuff like that,” said McGrath.

She said she lived with Smith for seven years. The last time she saw him, he was about 15.

But McGrath said even back then, the man now accused of murder, acted violently as a young boy.

“He could break a door or window. He was never abusive to his mother or anyone like that,” she explained.

McGrath said she’s tried to reach out to the family but can’t seem to get through. She, like many, are still in shock trying to understand why Smith, all of the sudden snapped.

“I never, never thought I would be talking to you or this would be happening to his family,” McGrath said.

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