A possible sighting of missing Orlando toddler Caylee Anthony is likely a case of mistaken identity.

The FBI investigated the tip and concluded that the girl seen isn't Caylee, who disappeared more than three months ago, according to MyFOXOrlando.com.

Investigators pored over surveillance photos of the child at a McDonald's in Tennessee, about 30 miles outside of Nashville.

Caylee's grandfather, George Anthony, also saw the pictures and said he doesn't think they're of his granddaughter either, MyFOXOrlando.com reported.

“It’s definitely not her,” he said. “I know it in my heart ... I know that even though it's been three months, it’s not her.”

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Caylee's mother, Casey Anthony, has been named a suspect in her daughter's disappearance, but has only been charged with child neglect and lying to investigators in the case.

She also faces unrelated check fraud charges and is currently at home with her parents on house arrest after several stints in the Orange County Jail.

Meanwhile, the State Attorney's Office is reviewing complaints about the money being spent on searching for Caylee, who was last seen in mid-June and would have turned 3 on Aug. 9.

At issue is the alleged misuse of funds in the Anthony case and possible charity fraud, but the office was mum on details, according to MyFOXOrlando.com.

On Monday, the protesters who have been a fixture on the Anthony family's lawn tried to force the family to confess that Caylee is dead.

The demonstrators believe 22-year-old Casey Anthony killed her small daughter and her parents, George and Cindy Anthony, are covering up the crime.

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