Orlando, Florida - Casey Anthony sat stone-faced most of the day. It's what trial-watchers and legal analysts have come to expect from the young Orlando mother throughout the high profile trial.
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But, today was different.
Today, her own father took the stand and talked about taking his own life and the extreme guilt he felt for "failing Caylee," he claimed.
George Anthony sobbed and wiped away tears when he talked about the first time he heard that his granddaughter's bones were discovered.
But, what about Casey's tears? Why didn't they come during that testimony?
What seemed to surprise people the most is that the 25-year-old never shed so much as a tear on Wednesday when her father cried through testimony and described in detail his suicide attempt.
The tears began to flow, however, when a grief expert took the stand.
Dr. Sally Karioth has had experience with 40,000 people, mainly dealing with dying and death
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She is a professor at Florida State University.
However, Dr. Karioth hasn't worked with anybody in this particular case.
After working with many people who have dealt with the loss of a child, Dr. Karioth pointed out that people grieve in various ways.
Specifically, she testified about ways mothers deal with that type of grief.
Dr. Kaioth said some will begin behaving in a risky manner, while others simply save everything that belonged to their child.
Defense attorney Dorothy Clay Sims began asking hypothetical questions.
Those questions seemed to bear a resemblance to Casey Anthony's story and the facts surrounding Caylee's disappearance, including the same type of family dynamic.
Dr. Kaioth said, "When we deal with families where there is a conspiracy of silence, as it were in those situations it's very likely that the response to a traumatic episode. In hypothetical situations, we can see that denial is a great helper."
Sims pointed out that many times young people will not grieve openly, referring to the behavior Casey displayed during those now infamous 31 days when Caylee was missing.
Sims brought up Casey getting a tattoo and partying.
During cross examination, Dr. Karioth pointed out that it's common for both extreme happiness and extreme sadness are both associated with grief.
Dr. Karioth even said sex is common as a sign of someone feeling a bit better.
Prosecutor Jeff Ashton asked, "Everything is consistent with grief in your opinion, right?"
Karioth admitted that she has not been given any facts about the case.
However, she did look up the case briefly just to review the case.