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MCKINNEY (CBSDFW.COM) – Testimony has begun in the murder case for a woman accused of killing her fiance’s 2-year-old daughter.

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Prosecutors say Melinda Muniz staged a home invasion at her Plano apartment before calling her fiance screaming for help. According to police, Mitch Ford then called 911 and directed Plano Police to Muniz’s apartment. When they arrived, they found Melinda face down, with her pants around her ankles. Her mouth was duct taped.

Officers also found 2-year-old Grace Ford in her bed, also face down, with her mouth duct taped. When officers found Grace, she had no pulse. She was taken to Plano Medical Center, where doctors were able to get her heart beating and she was placed on a ventilator.

According to testimony from Grace’s ER doctor, he noticed injuries to her genital area, and detectives ordered that doctors do a sexual assault exam on the toddler.

It was the victim’s father, Mitch Ford who gave the most emotional testimony of the day. He described learning of an affair between Muniz and her personal trainer the night before the murder.

Ford told jurors he found explicit text messages and naked photos exchanged on Muniz’s cell phone. He says confronted her the next day and broke up with her only hours before he got the call from her screaming that something was wrong.

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After the death of his daughter, Ford told jurors he began to drink a lot and continued a relationship with Muniz, all while she claimed to have amnesia. He said at one point he even held a gun to her head demanding to know what happened to his daughter. Eventually, police asked Ford to help them with their investigation of Muniz which led to her arrest.

Relatives of Grace’s biological mother, Emily Ward appeared in court Tuesday. They did not want to go on camera, but they gave us a written statement attributed to Emily Ward and her parents, Doug and Marilil Reeves.

It reads, “Although we are still deeply grieving for our daughter and granddaughter, Gracie, and continue to find it hard to believe she is gone, we are glad that this day has come when justice will finally begin to be served.”

“What we want, of course, is for Gracie to be with us but, since nothing we can say or do can bring her back, we look forward to justice being carried out. Grace deserves justice and it will bring to us some degree of closure.”

A jury of 8 women and 6 men are hearing the evidence.

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