In a murder case full of mysteries that have captivated the public, one of the biggest of all - the identity of Caylee Anthony's father - is STILL unclear.
In court on Thursday, defense attorney Jose Baez elicited gasps as he implied that Casey Anthony's own brother, Lee, could be the father of daughter.
The suspicion had enough merit that the FBI tested Lee Anthony to make sure he was not the father of Casey Anthony's slain daughter. He wasn't.
Nevertheless, the mystery of Caylee's father goes back to 2005, when Casey Anthony was pregnant - from a one-night stand, she told a neighbor.
According to police, she told Brittany Schieber she was seven months along before she realized she was pregnant and didn't know who the dad was.
Shortly after getting pregnant, Anthony started dating Jesse Grund. As the two grew closer, Grund started assuming the role of a expectant father.
In 2009, Grund said that he knew the timing of conception wasn't quite right, but that he thought it was "possible" that he could be Caylee's dad."For the first year or two of her life, I was dad," he said. "I was the father figure in her life, and I loved her more than anything. She was amazing."
"I had never been a father before."
After DNA disproved Grund's being Caylee's father, he was devastated: "That was really hard, because I just assumed that she was mine ... I loved Caylee so much, and finding out she was someone else's daughter was hard."
Even Anthony's close friends are clueless here.
Asked about paternity in 2008, Anthony's friend Lauren Gibbs told detectives, "Um, well, at first I thought it was Jesse. I don't know his last name."
"But then she told me later it was not and that it was somebody in the Army or something like that. But then she told me he died in a car accident."
Casey's mom, Cindy Anthony, seemed to agree with the car crash theory. "Caylee's father was in a terrible car accident," she said. "He is deceased."
Jesus Ortiz was a 21-year-old who dated Casey before he died in 2007. After he was named as Caylee's possible father, Ortiz's family was stunned.
"Miss Anthony never told the family Jesus might be the father," they said in a statement. "The family has never met her and does not know her."
Now that Caylee Anthony is gone, the matter of her paternity could always remain a mystery in a case with no shortage of unanswered questions.
Lawyers began laying out Casey Anthony's defense last week.