Investigators sifted the soil Friday in a wooded area where a child's skeleton was found near the home of missing Florida toddler Caylee Anthony.

Deputy Carlos Padilla, a spokesman for the Orange County Sheriff's Department, said that confirming the identity of the remains could take days, The Orlando (Fla.) Sentinel reported. Caylee's mother, Casey Anthony, was charged with her murder in October, three months after her daughter was reported missing.

Casey Anthony's lawyers said Thursday that they had been told the hair color and measurements of the remains match those of the missing 2-year-old.

The FBI has become involved with the search of the site, Padilla said.

"The shrubbery and undergrowth is really thick," he added. "They are sifting through to see if there is anything that connects this case."

Investigators also searched the house of Casey Anthony's parents, about a quarter-mile away, on Thursday. She and her daughter were living with Cindy and George Anthony when the little girl vanished.

Caylee was last seen in June. After her grandmother reported her missing, Casey Anthony told police the girl had been kidnapped by a babysitter.