Casey Anthony Reportedly Refuses to Reveal One Detail About Late Daughter Caylee

More than a decade after her remains were discovered near her family's home five months after her disappearance, one question still remains: who was Caylee Anthony's father? After her mother was charged with her murder, numerous details regarding Casey Anthony's life surfaced, though she never revealed who the father of her 2-year-old daughter was. That secret, according to one source, is one Anthony plans to take to the grave.

In a new report from PEOPLE, it is revealed that not even those closest to Anthony know who her late daughter's father was. A source said to be close to the 32-year-old, who still resides in Florida, told the outlet, "I don't know who the father was. According to the source, even years after Caylee's death and her murder trial, Anthony "doesn't talk about it." The identity of Caylee's father is something Anthony "will never tell anyone," according to the outlet's source, who added, "she'll take that secret to the grave."

Although Anthony has never, and likely never will, reveal the identity of Caylee's biological father, in the years since the toddler's death, rumors have swirled regarding his identity. Following Caylee's disappearance in June 2008, speculation arose that 21-year-old Jesus Ortiz fathered Caylee. Ortiz and Anthony had casually dated, though Ortiz tragically died in a car accident in 2007. After Caylee went missing, her maternal grandmother, Cindy Anthony, told the media that "Caylee's father was in a terrible car accident, he is deceased," and one of Anthony's friends, Lauren Gibbs, told detectives that Anthony told her that Caylee's father "died last year in a car accident."

According to YourTango, Ortiz's family claims they had neither met nor known of Anthony. Similar to Ortiz, Michael Patrick Duggan was also speculated to be Caylee's father. Duggan also died in a car accident. His mother, Donna MacLean, told the Daily Beast in 2011 that her son told her during a phone call in the summer of 2007 that he was Caylee's father.

Speculation also arose that Jesse Grund, Anthony's ex-fiance and her on-and-off boyfriend at the time of Caylee's birth, was Caylee's biological father. In a 2009 statement to PEOPLE, Grund said he believed it was "possible" Caylee was his. However, a subsequent DNA test proved he wasn't the father.

The notorious 2011 Florida v. Casey Anthony trial captured international attention, with Anthony being dubbed "America's most hated mom." Anthony was ultimately acquitted of the charges of first-degree murder, aggravated child abuse and aggravated manslaughter of a child. She was convicted on four misdemeanor counts related to lying to investigators, though those charges were later overturned. In the years since her acquittal, she has maintained a low profile.