In a strange twist in the tale that could all but nail Casey Anthony conclusively, it emerged that the alleged killer of the toddler daughter could have borrowed a plot from a fellow jail inmate to argue that Caylee Anthony drowned in the pool.

The prosecutors told the court on Tuesday a 15-month-old son of a fellow inmate of Casey’s had drowned in the family swimming pool and was found dead by the grandfather of the child. The incident took place in Orlando on Christmas Day 2007.

According to prosecutor Linda Drane Burdick, the new piece in the jigsaw puzzle is being investigated. The prosecution believes that the woman in question, April Whelan, may not have told Casey the story of the child's drowning, but she may have heard it from other prisoners.

In a remarkable coincidence, Casey's defense has argued that Caylee Anthony drowned in the pool and was found by grandfather George Anthony. Casey's attorney Jose Baez had presented a strikingly similar story of Caylee's death in his opening argument.

It was established that the 30-year-old Whelan, had been put in the same dormitory as Anthony at the Orange County Jail for five days in June 2009.

Casey Anthony is accused of murdering her daughter by applying chloroform first and sealing her mouth with duct tapes, looked away. Caylee's death took place in June 2008.

Casey Anthony denies the charges that she murdered her toddler daughter. She contends that Caylee drowned accidentally in the swimming pool. If she is found guilty of first degree murder, Casey Anthony could be sentenced to death by lethal injection.

He story is that she lied about Caylee's death because she was 'conditioned to lie'. She had also accused her father of sexually abusing her for years when she was a child, a charge George has denied in court.

The prosecution says Casey killed the little girl by suffocation and kept the dead body in the boot of her for several days. She then dumped the body in the woods near her parents' home.

On Tuesday, a forensic botanist testified in court that Caylee's remains possibly lay in the woods for at least two weeks before they were discovered.

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