Updated

The family of a little Florida girl who apparently vanished while she was sleeping is afraid she was taken by a pedophile cousin.

The mother and paternal grandmother of 5-year-old Haleigh Cummings said Friday the man in question is a cousin of Misty Croslin, the teenage girlfriend of Haleigh's father, Ronald Cummings.

Police are questioning the cousin, who is from Tennessee and was visiting when Haleigh disappeared before dawn Feb. 10, according to MyFOXOrlando.com.

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"What we've been told is that he's a sexual pedophile," said Haleigh's mother Crystal Sheffield. The child's grandmother, Teresa Neves, said Croslin described him as a "jerk" and she was worried.

"I couldn't tell you anything about him," a distraught Neves told reporters Friday, adding that she only knew of the cousin by his first name Joe. "I can't tell you how they could have taken her from a family that absolutely adores her."

The family's plea for the child's return came as news emerged about a tip from Tennessee called in by a woman claiming to have seen a man in a restaurant with a little girl resembling Haleigh, according to MyFOXOrlando.com.

The tipster, who reportedly phoned Knoxville detectives Sunday, said the man she saw was in a red Toyota RAV4 and appeared to be trying to shield the little girl with him.

Knoxville police said they didn't locate the car but turned the information over to Florida authorities on the case, according to MyFOXOrlando.com.

Putnam County investigators said they impounded a car in the case, but they wouldn't give a description of the vehicle, the station reported.

Sheffield told FOX News' Geraldo Rivera Saturday that Ronald Cummings had been abusive to her when she first got pregnant.

"He punched me in the back of the head and before then, he was verbal," she said. "I mean he was just very abusive."

Sheffield also said she was told by her cousin of an incident where Cummings apparently hit Haleigh after the child bumped into him or smarted off to him.

"She said he just backhanded her. And she fell flat on her face on the porch," Sheffield said.

Cummings, however, denies he had ever been abusive to Haleigh or Sheffield.

"Never, ever have I ever hit my child," he said. "Never, never have I ever hit any woman, period. Never."

On Thursday a sexual predator was arrested near the trailer home where Haleigh lives with 24-year-old Cummings, 17-year-old Croslin and Haleigh's little brother Junior.

Police said Timothy R. Loucakis was brought in on charges unrelated to the missing child.

"Word is getting out that we have a sexual predator in custody, and we do, but we have no reason to link it to Haleigh," said Putnam County Sheriff Jeff Hardy. He said Loucakis missed his curfew, but GPS tracking showed him "within his home zone" — and not near Haleigh — when she reportedly vanished.

Detectives are still "not excluding anybody" as a suspect in the girl's disappearance, Hardy said.

Loucakis was convicted of "promoting a sexual performance by a child" in May of 2001 and is currently listed as a sexual predator, according to the Florida Department of Law Enforcement Web site.

"What we're concerned about was he wasn't where he was supposed to be," Hardy said.

On Friday, police announced that the reward for information leading to Haleigh had risen to $20,000 but they offered no other details of their progress in solving the mystery.

Authorities have been investigating a tip that casts doubt on a story told by Croslin that she was home when she discovered the child missing. The source said she wasn't in the trailer when Haleigh vanished last Tuesday. Investigators say they're looking into the report.

They're also studying inconsistencies in descriptions of what the girl was last seen wearing. Croslin told them Haleigh had a pink shirt on the night she vanished, but police said this week they have that item of clothing in their possession.

The girlfriend has also reportedly told different stories to cops and the media about the timing of her discovery that Haleigh was gone and where she and the child were that night.

Cummings and Croslin have both taken lie detector tests. They told FOX News they "passed" the polygraphs. Police haven't released the results.

The family has been at the center of investigations done by the state child welfare agency, but details of those cases haven't been disclosed because of confidentiality laws.

Neves said her son would never hurt Haleigh and pleaded Friday for her granddaughter's kidnapper to bring her home.

"I want to say to my baby, we love you sweetheart, and we will find you," she said through tears.

Click here for more on this story from MyFOXOrlando.com.