By . Ashley Collman . A 28-year-old woman recounted the night she watched three members of her family die at the hands of her jealous fiance who accused her of cheating, as his murder trial began Wednesday in Cook County, Illinois . Prosecutors say D'Andre Howard, now 26, showed up to his girlfriend's family home in the early hours of April 17, 2009 and turned it into a 'house of horrors' - telling Amanda Engelhardt's family that he was 'going to make them pay' before fatally stabbing her sister, father and grandmother. Howard confessed to the murders, but his public defenders argue that he should be found not guilty by reason of insanity. Scroll down for video . Trial begins: D'Andre Howard (left) is currently on trial for the 2009 murder of Amanda Engelhardt's (right) sister, father and grandmother. Howard and Amanda were engaged at the time of the fatal stabbings, which allegedly started after Howard accused Amanda of cheating . Her side of the story: Howard's trial began Wednesday, and his public defenders are arguing that he should be found not-guilty by reason of insanity. Amanda was the first to testify, and is pictured on the left in court on Wednesday . Family photo: Amanda (bottom left)  recounted in court the night she watched her fiance kill three members of her family. Father Alan, 57 (top left), sister Laura, 18 (center), and maternal grandmother Marlene Gacek were stabbed to death by Howard. Her mother Shelly, now 57 (top right), was also stabbed but survived and brother Jeff (bottom right) was away at school . 'He does have a mental illness preventing him from appreciating the criminality of what he was doing' Public defender Georgeen Carson said. Amanda was the first to testify Wednesday about the night of the murders, as her ex-fiance sat calmly in court. Amanda told the jury that she and her boyfriend of three years had gotten into a fight the night before, when he accused her of cheating on him at the apartment they shared with their then 8-month-old daughter. Howard allegedly ordered Amanda to leave and take the baby with her, so Amanda's parents Alan and Shelly Engelhardt picked her and the baby up and drove her back to their Hoffman Estates home. The fight: The night before the attack, Howard and Amanda allegedly got into a fight when he accused her of cheating. The two lived together with their then 8-month-old daughter. Amanda is pictured with their daughter in the above photo posted to Facebook . However, Howard showed up at the family home later, around 1:45am, when he continued to fight with Amanda. Amanda finally got some rest when she thought he left, but was awakened soon by Howard who was holding a knife to her throat. Howard then brought Amanda down to the home's den, where he tied her and her mother Shelly up and threatened to kill the rest of the family in front of them. 'He said because Amanda ruined his family, he was going to ruin ours,' Shelly, now 57, said in her testimony Wednesday. 'He told them he was going to make them pay,' Cook County Assistant State’s Attorney Kristin Piper said. He went on to wake up Amanda's 18-year-old sister Laura, and tied her up as well. At some point he untied Laura, and she quickly grabbed his knife and stabbed him. This caused him to react 'on a very primitive level,' his defense said. Fighter: Howard tied up Amanda, her mother, and then her sister Laura (pictured with their father above). He untied Laura at one point and she grabbed the knife and stabbed him. He fought the knife back and snapped - stabbing her several times. Laura did not survive . The two fought for the knife and Howard won. He 'became so angry, he repeatedly stabbed Laura in the chest, over and over and over,' Assistant State's Attorney Kristin Piper said. When mother Shelly started screaming, he also stabbed her and she would spent the rest of the bloodbath drifting in and out of consciousness. Her screaming caused both Amanda's father Alan, 57, and maternal grandmother Marlene Gacek, 73, to wake up and move towards the den. Protecting his family: Howard fatally stabbed Alan Engelhardt when he woke up and responded to his wife's screams. Pictured above in a family photo his widowed wife posted on Facebook . Howard first stabbed Marlene in the kitchen and then went on to slash Alan's throat. Laura, still conscious, and her sister started begging Howard to call 911, but he refused for an entire hour as their family members suffered painful deaths. Eventually Howard relented and called police, telling an operator what he had done. By the time police arrived, it was too late to save Amanda's sister, father or grandmother. Mother Shelly survived but was seriously injured. Too late: Howard eventually called police, and told a 911 operator that he committed the murders. By the time police arrived on the scene, it was too late to save Amanda's sister, father or grandmother . In her testimony on Wednesday, Amanda described her ex-fiance's behavior in the aftermath of the stabbings. She says he kept pacing between the den and the kitchen, apologizing 'off and on to everybody', saying 'he was very sorry demons had gotten him'. Howard allegedly tried to hide the murder weapon, but did not flee. When police arrived, they found him lying down between Shelly and Laura. Amanda also talked about her sister Laura's last words to Howard. She says he was laying down next to her when he apologized, and that Laura said 'that she forgave him'. Shelly also testified on Wednesday, and talked about her family's relationship with the young man. She said they treated him like another member of the family, and that he even lived with them for about a month at one point. The Engelhardts invited him to family events and church. One of the family: Shelly Engelhardt told the jury that she treated Howard like a family member, and that he was invited to family events and church. Frames memorialize the husband, daughter and mother she lost in the attack, as shared on Facebook . Howard's defense team is trying to win the case by proving he was insane at the time of the stabbings. He apparently tried to fire his defense team the day before the jury was seated. Public defender Carson says his mental illness 'boiled up and led him to kill the only family he ever had'. Howard remained calm as he listened to his ex-fiancée and her mother testify, but did cover his face at one point. Amanda's brother Jeff Engelhardt, who was away at school at the time of the stabbings, was in court on Wednesday to support his sister and mother. 'I am really proud of her,' Jeff told CBS Chicago of his sister. 'She was really brave and I knot it is tough for her.' Brother: Amanda's brother Jeff, who was out of town at the time of the stabbings, was in court on Wednesday to support his sister and mother .
D'Andre Howard killed three members of fiancée Amanda Engelhardt's family in the early hours of April 17, 2009 .
The 26-year-old's murder trial began Wednesday in Cook County, and Amanda was the first to testify .
She told the jury of the night Howard tied her up and stabbed her sister, father and grandmother to death and seriously injured her mother .
Howard, her boyfriend of three years and the father of their then 8-month-old daughter, had accused her of cheating .
His defense asked the jury to find him not-guilty by reason of insanity .
By . Ashley Collman . A 28-year-old woman recounted the night she watched three members of her family die at the hands of her jealous fiance who accused her of cheating, as his murder trial began Wednesday in Cook County, Illinois . Prosecutors say D'Andre Howard, now 26, showed up to his girlfriend's family home in the early hours of April 17, 2009 and turned it into a 'house of horrors' - telling Amanda Engelhardt's family that he was 'going to make them pay' before fatally stabbing her sister, father and grandmother. Howard confessed to the murders, but his public defenders argue that he should be found not guilty by reason of insanity. Scroll down for video . Trial begins: D'Andre Howard (left) is currently on trial for the 2009 murder of Amanda Engelhardt's (right) sister, father and grandmother. Howard and Amanda were engaged at the time of the fatal stabbings, which allegedly started after Howard accused Amanda of cheating . Her side of the story: Howard's trial began Wednesday, and his public defenders are arguing that he should be found not-guilty by reason of insanity. Amanda was the first to testify, and is pictured on the left in court on Wednesday . Family photo: Amanda (bottom left)  recounted in court the night she watched her fiance kill three members of her family. Father Alan, 57 (top left), sister Laura, 18 (center), and maternal grandmother Marlene Gacek were stabbed to death by Howard. Her mother Shelly, now 57 (top right), was also stabbed but survived and brother Jeff (bottom right) was away at school . 'He does have a mental illness preventing him from appreciating the criminality of what he was doing' Public defender Georgeen Carson said. Amanda was the first to testify Wednesday about the night of the murders, as her ex-fiance sat calmly in court. Amanda told the jury that she and her boyfriend of three years had gotten into a fight the night before, when he accused her of cheating on him at the apartment they shared with their then 8-month-old daughter. Howard allegedly ordered Amanda to leave and take the baby with her, so Amanda's parents Alan and Shelly Engelhardt picked her and the baby up and drove her back to their Hoffman Estates home. The fight: The night before the attack, Howard and Amanda allegedly got into a fight when he accused her of cheating. The two lived together with their then 8-month-old daughter. Amanda is pictured with their daughter in the above photo posted to Facebook . However, Howard showed up at the family home later, around 1:45am, when he continued to fight with Amanda. Amanda finally got some rest when she thought he left, but was awakened soon by Howard who was holding a knife to her throat. Howard then brought Amanda down to the home's den, where he tied her and her mother Shelly up and threatened to kill the rest of the family in front of them. 'He said because Amanda ruined his family, he was going to ruin ours,' Shelly, now 57, said in her testimony Wednesday. 'He told them he was going to make them pay,' Cook County Assistant State’s Attorney Kristin Piper said. He went on to wake up Amanda's 18-year-old sister Laura, and tied her up as well. At some point he untied Laura, and she quickly grabbed his knife and stabbed him. This caused him to react 'on a very primitive level,' his defense said. Fighter: Howard tied up Amanda, her mother, and then her sister Laura (pictured with their father above). He untied Laura at one point and she grabbed the knife and stabbed him. He fought the knife back and snapped - stabbing her several times. Laura did not survive . The two fought for the knife and Howard won. He 'became so angry, he repeatedly stabbed Laura in the chest, over and over and over,' Assistant State's Attorney Kristin Piper said. When mother Shelly started screaming, he also stabbed her and she would spent the rest of the bloodbath drifting in and out of consciousness. Her screaming caused both Amanda's father Alan, 57, and maternal grandmother Marlene Gacek, 73, to wake up and move towards the den. Protecting his family: Howard fatally stabbed Alan Engelhardt when he woke up and responded to his wife's screams. Pictured above in a family photo his widowed wife posted on Facebook . Howard first stabbed Marlene in the kitchen and then went on to slash Alan's throat. Laura, still conscious, and her sister started begging Howard to call 911, but he refused for an entire hour as their family members suffered painful deaths. Eventually Howard relented and called police, telling an operator what he had done. By the time police arrived, it was too late to save Amanda's sister, father or grandmother. Mother Shelly survived but was seriously injured. Too late: Howard eventually called police, and told a 911 operator that he committed the murders. By the time police arrived on the scene, it was too late to save Amanda's sister, father or grandmother . In her testimony on Wednesday, Amanda described her ex-fiance's behavior in the aftermath of the stabbings. She says he kept pacing between the den and the kitchen, apologizing 'off and on to everybody', saying 'he was very sorry demons had gotten him'. Howard allegedly tried to hide the murder weapon, but did not flee. When police arrived, they found him lying down between Shelly and Laura. Amanda also talked about her sister Laura's last words to Howard. She says he was laying down next to her when he apologized, and that Laura said 'that she forgave him'. Shelly also testified on Wednesday, and talked about her family's relationship with the young man. She said they treated him like another member of the family, and that he even lived with them for about a month at one point. The Engelhardts invited him to family events and church. One of the family: Shelly Engelhardt told the jury that she treated Howard like a family member, and that he was invited to family events and church. Frames memorialize the husband, daughter and mother she lost in the attack, as shared on Facebook . Howard's defense team is trying to win the case by proving he was insane at the time of the stabbings. He apparently tried to fire his defense team the day before the jury was seated. Public defender Carson says his mental illness 'boiled up and led him to kill the only family he ever had'. Howard remained calm as he listened to his ex-fiancée and her mother testify, but did cover his face at one point. Amanda's brother Jeff Engelhardt, who was away at school at the time of the stabbings, was in court on Wednesday to support his sister and mother. 'I am really proud of her,' Jeff told CBS Chicago of his sister. 'She was really brave and I knot it is tough for her.' Brother: Amanda's brother Jeff, who was out of town at the time of the stabbings, was in court on Wednesday to support his sister and mother .
recounted the night she watched three members of who accused her of cheating, as his murder trial began Wednesday in Cook County, Illinois . to his girlfriend's family home in the early hours of April 17, 2009 and turned it into a of Amanda Engelhardt's (right) sister, father and that he should be found not-guilty by reason of insanity. Amanda was the first to testify, and is grandmother Marlene Gacek were stabbed to death Amanda told the jury that she and her boyfriend of three years had gotten into a fight the night 8-month-old daughter. Howard allegedly ordered 18-year-old sister Laura, and tied her up as her mother, and then her sister Laura (pictured