A private investigator is looking into whether a possible sighting of missing Florida toddler Caylee Anthony has any merit.

A photograph of a child resembling the 3-year-old girl taken at a west Florida mall was released on Friday, according to MyFOXOrlando.com.

The picture, reportedly snapped by a shopper at the mall, was given to D & A Investigations, a firm that is working with the Anthony family. It has also been turned over to Orange County sheriffs and the FBI.

D & A is asking anyone with any information on the potential sighting to call 1-888-231-5618 or email cayleetips@yahoo.com.

Click here for photos.

On Thursday, the lawyer for the tot's grandparents, George and Cindy Anthony, quit the job, saying only Caylee's imprisoned mother knows the truth about what happened.

Mark NeJame indicated that he was off the case because of disagreements with the Anthonys. Their daughter Casey Anthony is jailed on first-degree murder charges in Caylee's presumed death.

NeJame said there was little more he could do to help them in the search for the child.

The Anthonys issued a statement saying they respect NeJame's decision.

Casey Anthony is awaiting a January trial on first-degree murder, manslaughter and other charges. Her little girl disappeared in June, but her family didn't report her missing for about a month and her body has not been found.

Anthony said she left her daughter with a baby sitter, who has also never been located. Police believe she made the story up.

Caylee's grandparents continue to insist that their granddaughter is still alive.

This week both the prosecution and the defense released witness lists of those whose testimony they'll ask for at trial. The prosecution named more than 80 people, including George and Cindy Anthony and lead defense attorney Jose Baez. The defense listed only three witnesses, including a forensics expert and a criminal justice professor.

Casey Anthony has pleaded not guilty to first-degree murder, aggravated child abuse, aggravated manslaughter and four counts of lying to investigators about Caylee's disappearance.

Forensic tests released last month confirmed that hair linked to Caylee and found in the trunk of Anthony's Pontiac Sunfire came from a decomposing body. Other DNA evidence also suggests that a corpse was in the trunk.

Click here for more from MyFOXOrlando.com.

Click here for the witness list from MyFOXOrlando.com.

Click here for Casey Anthony's indictment.

Click here for a timeline of the Casey Anthony case.

Click here for other documents released.

The Associated Press contributed to this report.