CLEVELAND (May 29) - A coroner ruled Thursday that R&B singer Sean Levert died of natural causes after falling ill in jail, and his family reacted by saying his death possibly could have been prevented.

Levert suffered from various ailments, the Cuyahoga County coroner's ruling said. Attorneys for Levert's widow say sheriff's department records they reviewed show he wasn't given his anti-anxiety medication while in jail or seen by a doctor, which might have prevented his death.

Levert, a member of the 1980s R&B trio LeVert and son of lead O'Jays singer Eddie Levert, died at age 39 at 11:57 p.m. March 30 at a hospital, about an hour after he was taken from the Cuyahoga County jail. He was serving a 22-month sentence for failure to pay child support.

Levert's family had questioned officials' account that Levert had been acting strangely and was restrained before he fell ill. In his ruling, county Coroner Frank Miller ruled out foul play or trauma.

Miller said Levert died from complications of sarcoidosis, an inflammatory lung disease that produces tiny lumps of cells in the body's organs. The coroner said Levert also suffered from other conditions, including heart disease, high blood sugar and withdrawal from alprazolam, a drug used to treat anxiety disorders and panic attacks that is better known under the trade name Xanax.

After Levert died, jail warden Kevin McDonough said he had been sick and guards were watching him because he had been acting strangely. When he started pounding on his cell door, guards strapped him in a restraint chair, McDonough said. Levert's breathing became shallow and he was taken to the hospital.

"He was exhibiting classic signs of Xanax withdrawal," attorney Daryl Dennie said. "A doctor would have been able to recognize these problems. Had he been able to see one in that week's time things could have been different."

Dennie and lawyer David Malik, who represent Levert's widow, Angela Lowe, said they reviewed documents in the coroner's office showing that Levert brought a bottle of Xanax with him to the jail.

"They inventoried it and they never gave it to him," Malik said. "He requested it during the time he was in jail."

The coroner's office would not release the documents publicly on Thursday.

Messages seeking comment from Chief Deputy Douglas Burkhart at the sheriff's department and county Prosecutor Bill Mason were not immediately returned.

Malik and Dennie would not comment on possible legal action until they complete their investigation. Malik said the family may ask the FBI to investigate.

FBI spokesman Scott Wilson said in April that agents were willing to meet with Levert's family. Wilson said Thursday that the FBI was never contacted by the family.

Levert and his brother Gerald formed LeVert in the 1980s with childhood friend Marc Gordon. Their hits included "Baby I'm Ready," "(Pop, Pop, Pop, Pop) Goes My Mind" and "Casanova."

His brother died in 2006 at age 40 of an accidental mix of prescription and over-the-counter drugs.

Sean Levert, who was trying to start the group LeVert again, had pleaded guilty in March to six counts of failure to pay child support. He was accused of failure to pay $89,025 to children ages 11, 15 and 17.

He had pleaded guilty in 1995 to drug abuse and was placed on probation and required to get treatment.

Levert's widow released a written statement Thursday saying: "Sean was loved by many and both his family and fans are saddened beyond comprehension. Sean Levert did not die as a result of illegal drug usage."