But now Smith, 36, is being cared for by corrections officers as he sits in a prison cell, charged with the savage slaying of Melissa Ketunuti, a doctor at the Children's Hospital of Philadelphia.
Ketunuti, 35, was found strangled in the basement of her Center City house Jan. 21. Her arms and legs were tied and her body set ablaze. Two days later, police homed in on Smith, an exterminator who they said was called to Ketunuti's house for a job.
When police charged Smith with murder on Thursday, they said he gave a statement in which he had an argument with Ketunuti that had caused him to lash out at her. Reports have said that Smith told police he felt that Ketunuti had belittled him.
Elliott said she could envision Smith getting easily offended.
"I never knew a real violent side to him. I could see him getting in someone's face, but not murdering someone," she said. "Obviously, things have escalated since I knew him."
Smith had a relatively clean record, aside from a few traffic offenses, a driving-under-the-influence charge and a guilty plea to a disorderly-conduct charge.
Wayne Welsh, a criminal-justice professor at Temple University, said the circumstances of Ketunuti's slaying and the fact that Smith had no violent record are "extremely unusual."
"Usually when you're talking about somebody who has the capacity to commit that kind of violent murder, it would be extremely unusual if we don't find anything in his history indicating aggressive and violent behavior," Welsh said. "I'd be shocked if that history doesn't start to come up, even if it's not some type of criminal history."
Until now, little has been known about the man who was arrested at the Levittown home he shared with his daughter, his fiancee and her parents.
Elliott said she began dating Smith's brother in 1998, married him in 2001 and divorced in 2004.
She's had little contact with the Smith family since then. Elliott, who has remarried, lives in Lancaster County and owns a housecleaning referral agency.
She had not heard about Ketunuti's death until her current husband, a "news hound," came home Friday and asked if her ex had a brother named Jason who lived in Levittown. He then told her to go online.
'Like a ton of bricks'
"My heart just sank. It was just so surreal," she said. "I had to read about everything at once. It just hit me like a ton of bricks."
Elliott said she got to know Jason Smith when she and Seneca Smith would go out on double-dates with Jason Smith and his then-girlfriend, who is now a law-enforcement officer.
At the time, Smith was living with his mother. In fact, for most of the time that Elliott knew Smith, he lived with his mother, who had 14 cats and eight dogs in her house, she said.
At one point, when their courtship was on the rocks, Seneca Smith moved into his own apartment, Elliott said. Jason moved in with his brother, but that didn't last long, because Seneca discovered that his brother was making calls to sex-chat lines on Seneca's dime, Elliott said.
Jason Smith racked up about $1,000 in bills from 1-900 numbers, she said.
"He never really acted like it was a big deal, and he certainly never gave us any money back," she said. "He never really seemed to have money. I don't remember him having a job. He was always kind of mooching off of someone."
When Elliott and Seneca Smith, an ex-Marine, decided to marry, Jason Smith was asked to be the best man at their wedding.
"I remember his speech. It was so stupid, and it was so short," she said. "He said, 'I just one day hope I can be as happy as the two of you.' "
Even though Elliott requested a dry wedding, when she went to the reception she discovered that the Smith family had "gone behind my back" and brought in alcohol.
"There were kegs and wine everywhere," she said. "They were all heavy drinkers and wanted the alcohol there."
Kathleen McGrath, 61, of Danboro, Bucks County, dated Jason Smith's mother, Sharon Smith, and lived with the family and her own two sons in Bucks County and Florida between 1984 and 1991.
McGrath said there was not a drop of alcohol in the house when they lived together.
"I knew Sharon to be a very devoted mother - she made decisions and choices for the best interest of her children," McGrath said. "She sacrificed as a single parent, but she was always there."
Later in his life, alcohol was "definitely" an issue with Jason Smith, Elliott said, but she saw no signs of drug use. Court records show that Jason Smith's DUI offense in 2004 involved both alcohol and drugs.
Elliott said that she knew Jason Smith's son, and that shortly before she separated from Seneca, Jason impregnated another woman."He loved his kid," she said. "When I knew him, that kid was his world."
According to what Elliott said her ex-husband told her, the Smith boys didn't have an ideal childhood.
She said that both boys were given their mother's maiden name and that they had different fathers. Jason knew who his father was, Elliott said, but he did not have a relationship with him.
Elliott said Seneca Smith told her that when he and Jason were children, his mom would make them go to the corner store and steal groceries because they didn't have any money. If they didn't go, she'd hit them with a frying pan. Elliott said that when she confronted their mother about the accusation, she denied it.
McGrath said Sharon Smith was never abusive.
"She disciplined the children, but she wasn't abusive and she wasn't strict," McGrath said. "It was just normal family dinners together. She tried to make the best decisions for the interest of what each child needed."
McGrath said that with four boys in one house, Jason Smith always seemed to be the one getting caught in trouble, but it was never serious or "stuff we couldn't handle as a family."
"I watched Jason grow into a teenager, and it was like he was really getting his life together," McGrath said.
But Elliott said Seneca Smith told her that Jason had committed a sexual assault as a juvenile and had to be placed in a special school.
When she knew him, Elliott said, Jason Smith wasn't physically abusive to the women he dated.
"He was more rude and disrespectful than abusive and, you know, just because of his nonambition it turned a lot of girls off," she said.
McGrath said she last saw Jason Smith around 1992. She and Sharon Smith, although no longer dating, were living in the same apartment complex and Jason would come over to walk her dog, she said.
"There's nothing to make Jason out to be a monster," she said.
Elliott, for her part, said it "really does freak me out" that someone she knew is accused of something so heinous.
"Every once in a while, I'll remember and think, 'Oh, my gosh, this is going on now,' " Elliott said. "I knew him. He was family."
- Staff writer Morgan Zalot
contributed to this report.
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