"20/20" continues with the perfect nanny. Reporter: In the hours after Michele Macneill's death, pleasant grove police detectives see no reason to treat the bathroom where she died like a crime scene.... See More
"20/20" continues with the perfect nanny. Reporter: In the hours after Michele Macneill's death, pleasant grove police detectives see no reason to treat the bathroom where she died like a crime scene. They collect no evidence from the Macneill house and the only person they interview is her husband, martin, who they know as a well-established local doctor. He tells them he believes his wife "Passed out while preparing the tub." I thought that, if this is a healthy woman that died that there would be some sort of big police investigation. Their police report into my mother's death is about 2 1/2 paragraphs. Reporter: The medical examiner determines that "Hypertension" and an existing heart infection called "Myocarditis" caused Michele's heart to fail. In other words -- death by "Natural" causes. Natural causes, she's not an old woman. She just turned 50 years old. I mean, she, she had a few issues. She had a little bit of high cholesterol, some high blood pressure. Reporter: Police close the case. Alexis and Rachel are stunned. But their father is moving on, and quickly. He arranges a funeral within three days. Two days after, he's back at work. Alexis and Rachel say they offered to come home to care for the four younger Macneill children. Their father announces he will hire a nanny. And he already seems to have one in mind. And he said "Oh, I found the perfect nanny." And I said, "What's her name?" And he said, "Oh, I think it's, Jillian?" And I said "Dad? Gypsy Jillian Willis?" I said, "I know that woman. I know mom was worried you were having an affair with her and you are not to bring her in the home." Reporter: But martin would not be deterred. He calls a family meeting. And he said, "There is going to be, uh, an interview for a nanny. And there was only one candidate and that was gypsy. Gypsy. Reporter: Imagine that. Yeah. And she got the job. She didn't cook, she didn't clean, she didn't take care of the children in any way. Reporter: Why did you move into the home? Martin told me that he needed help with his younger children. Reporter: Were you still sleeping with him? I was. Reporter: So, were you the nanny or were you the girlfriend? I moved in to help with the kids. When we had opportunity, I still slept with him. Reporter: So you were both? If you want to look at it like that. Reporter: But martin's daughters didn't like the look of that one bit. She walked into the house like she owned the place. And then when I questioned my dad and said, what's going on? He said, "Oh, she's a guest in our home and how dare you question me." He said, "If you fight me, I'm going to get you thrown out of medical school." And he started threatening me. "I'm going to take you down." I was told that I needed to leave the home because I, I wasn't nice to gypsy. He wanted to make it known that it was either gypsy or his children and he chose the "Nanny." Reporter: Three months after moving into the Macneill home, gypsy took martin back to Wyoming to meet her parents -- Harold and Vicky Willis. He said, "I never loved Michele, but I love gypsy." And I said, "But you had a family with Michele." He says, "Actually, I loved her as a friend, I loved her as a sister, but I never loved her like I love gypsy." Reporter: During that trip martin proposed to gypsy in front of her family. Gypsy's sister, Julie, was there. He gives this grand speech about how he loved her, and how he loved her from the moment he saw her and he knelt and proposed to her, and gypsy cried. It was very fairy tale. Reporter: This was the man who had been telling you just a couple months earlier that he had the perfect life and the perfect wife. Yeah. Reporter: So you must have been shocked when three months after she died he proposed marriage to you? I wasn't shocked. It just, like I said, it seemed very natural. It seemed like a natural progression. I believed he loved his wife. I didn't -- I didn't suspect anything unusual. Reporter: He never told you, I wish I was never married to Michele. He never said that. Reporter: "I wish Michele was dead"? No, he never said that. Reporter: "I'd rather be with you and not Michele"? He didn't say that. Reporter: Martin didn't say he'd rather be with gypsy, but was he thinking it? And what was she thinking? So don't you think it's a little funny that he goes from saying, "I love Michele," to, "Oops, she died, move in, let's continue sleeping together while you take care of my kinds, and will you marry me?" I realize that looks pretty cold on the outside. Reporter: Cold -- gypsy's own sister Julie goes even further. I would consider gypsy to be a deceptive, malevolent, malicious, calculating person. Reporter: Calculating and violent. Julie says gypsy had feuded with her and other family members for years. And even gypsy admits to having a fistfight with her mother over ownership of a dog -- the last time she ever saw her family. I was bruised from head to toe. I had a sprained knee, I had choke marks around my neck. She lunged forward and she bit me on my upper left bicep. A bad bite. You could count every single tooth mark. She doesn't care who gets hurt. She doesn't care what circumstances are ruined. Reporter: Fist-fighting is one thing, but could gypsy have gone so far as to help martin kill Michele? If she sees something she wants, she will rationalize to herself to the point that she will get that no matter what stands in her way. Reporter: Those are your family. I know. Reporter: They think that you're capable of murder. They are horrible and they are hateful. It is appalling that my family would say such things, and I think it is completely unfounded and unjust. Reporter: Julie Willis said that gypsy found the perfect match in martin Macneill. In a bad way, they were perfect for each other. Together, I believe that they are perfectly capable of killing Michele. They're like a pack of dogs, one dog alone might be malicious, might take a nip out of things, but two dogs together hunting
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