The father of missing girl Haleigh Cummings pleaded guilty Friday morning to three of five drug trafficking charges against him in exchange for him agreeing to testify in any future criminal trial involving the disappearance of his daughter.

Video:Related Story:Attorney Told Cousin Killed Haleigh

Ronald Cummings, along with his ex-wife, Misty Cummings, her brother, Hank Croslin Jr., and two other people were arrested in January after an undercover drug sting by St. Johns and Putnam County detectives. Misty and Hank have pleaded no contest to the charges. Croslin received a 15-year sentence and Misty Cummings faces sentencing in October.

Ronald Cummings, 26, could face a maximum of 90 years in prison. He will be sentenced Sept. 24.

All three are central figures in the disappearance of Ronald Cummings' 5-year-old daughter in February 2009. After an Amber Alert, weeks of exhaustive searching and an investigation involving more than 4,000 leads, Haleigh remains missing. In April, the Putnam County sheriff said she is likely dead and described the case as a homicide investigation.

Earlier this week, attorneys for both Misty Cummings and Hank Croslin said their clients have told investigators a similar story of what happened the night Haleigh disappeared. They both said that a Croslin cousin who lives in Tennessee placed the screaming girl in a black bag and took her from Cummings' mobile home.

That cousin, Joe Overstreet, has been questioned at least twice by detectives, but never charged or named a suspect in Haleigh's case.

Terry Shoemaker, Ronald Cummings' attorney, told Channel 4's Tarik Minor that his client isn't buying his ex-wife and brother-in-law's account of Haleigh's disappearance.

"Ronald has a hard time believing someone would go to the house to get a gun and take a child instead," Shoemaker said. "He questions that aspect of it."

Misty Cummings and Hank Croslin's mother, Lisa Croslin, said that Overstreet should be brought back to Florida to be interrogated.

Ronald Cummings' attorney said that if Haleigh's body is never found but police are able to make an arrest, testimony may be basis of a criminal prosecution. He said Ronald Cummings' relationships with each party is important in developing a timeline leading up to Haleigh's disappearance.

"If there ever was a trial in Haleigh's disappearance, they could ask him to come back and testify on the state's behalf," Shoemaker said.

Cumming's ex-wife and Haleigh's mother, Crystal Sheffield, who attended Friday's hearing, said she is holding out hope her daughter is alive.

"I don't care if they're in prison or not, but the truth needs to come out to bring my baby home," Sheffield said.