Casey Anthony suffered grand mal seizures, her mother revealed to "Dr. Phil" host Phil McGraw on an episode that aired Tuesday, that Cindy believes may have caused her daughter to suffer a mental breakdown when 2-year-old Caylee disappeared.
Dr. Phil thinks that is nothing more than Cindy Anthony refusing to accept reality.
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"I think it's denial of the highest order,'' McGraw told TODAY's Matt Lauer on Tuesday. "It's like, 'I'm going to find some reason to say this was involuntary on (Casey's) part, whatever it is she did.''
Casey Anthony, who was acquitted of the murder of her daughter in early July, has a history of seizures, her mother said. Anthony suffered one in 2008 when she was released on bond from check fraud charges, and had previously had one in 2007. Casey was examined by doctors after the first seizure in 2007, but nothing serious was found, according to Cindy.
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"I don't know why she's having a seizure,'' Cindy told Dr. Phil in an interview alongside her husband, George. "Does she have a brain tumor? Were the seizures caused by stress? I don't know what happened, and that's what I want to find out down the road.''
Grand mal seizures don't cause erratic behavior or lies, medical experts say. Casey lied to her family and authorities about Caylee's disappearance, which was not reported until 31 days after it occurred.
"If the patient is fully recovered after a seizure, there shouldn't be any changes in their personality or behavior,'' Dr. Enrique Serrano of the University of Miami School of Medicine told NBC News.
Anthony's history of seizures was not brought up by defense attorneys during the trial, although her mental stability was examined to make sure she was fit to stand trial. Dr. Phil thinks it is just Cindy Anthony trying to find a way to rationalize her daughter's actions. Cindy believes that something happened to Caylee that triggered a break in Casey, rather than the other way around.
"When I confront her with that, she comes up with another excuse, another excuse, another excuse,'' Dr. Phil said.
Another one of Cindy's theories revolves around a post-partum condition.
"Looking back now, I'm almost wondering if she didn't develop post-partum schizophrenia or some type of issue after her pregnancy,'' Cindy said.
One thing that is clear: Cindy was angry when Casey first told her that Caylee had been missing for 31 days.
"My worst nightmare had just unfolded in front of me,'' Cindy said. "I just screamed at her, and I said 'What the hell are you talking about?' I said, 'What do you mean you haven't seen Caylee?' I wanted to go choke her or hit her and I just went over there and punched the bed as hard as I could to get my anger out.''
Cindy offered an alternate theory regarding a neighbor's statement that Casey allegedly borrowed a shovel on the day that Caylee, who was eventually found buried in nearby woods, disappeared. Casey, Cindy said, had borrowed the shovel to cut a piece of bamboo in the backyard. Another possibility: The shed was locked and she needed the shovel to break in. The possibility that Casey used the shovel to bury her child was not considered.
"It is beyond illogical to not say, 'I have to consider that that's a possibility,'' Dr. Phil told TODAY.
Further complicating the theories: George and Cindy have differing versions of the story. While Cindy says that the neighbor watched Casey for the hour she used the shovel, George claims that the neighbor did not watch her - and that the shovel was returned later.