The family of 18-year-old Nolan Wells is demanding answers after hiring audio experts to examine a distress call made from a boat on the day he disappeared, raising fresh questions about what happened during the final hours before his body was found.

Civil rights attorney Ben Crump announced Thursday that the family has retained forensic audio engineers to analyze the July 4 recording, which captures a call for help from a boat taking on water near Mississippi's Horn Island, where Wells was last seen alive.

The call, released this week by the Mississippi Department of Marine Resources, features someone pleading for assistance after a bilge pump failed.

"Our bilge pump stopped working. We're sinking. Can y'all please come?" the caller says, adding that about seven people were on board.

But before rescuers arrived, a Sea Tow captain was told by a relative of the boat's owner that those aboard had fixed the problem and no longer needed help.

Exactly who was on the boat, what happened after the call and whether it is connected to Wells' disappearance remain unanswered.

Authorities have said witnesses told investigators Wells was not on the boat when it left Horn Island, but have released few additional details about the timeline of his final hours.

Crump said the family is also asking prosecutors to bring in outside experts to examine the cellphones of the friends who traveled with Wells to the island.

"We will not rest until we get answers," Wells' mother, Christine Wonsley, said Thursday.

The Black teenager traveled to the uninhabited island with a group of white high school friends on July 4 but never returned to the mainland with them. His body was found floating off the island two days later.

Jackson County Sheriff John Ledbetter said shortly after the discovery that Wells' friends were cooperating with investigators and that authorities did not suspect foul play. The investigation remains open.

An independent autopsy commissioned by Wells' family was unable to determine how he died. The official autopsy has not been released and will remain sealed until a grand jury reviews the evidence, a standard procedure in Jackson County.

The lack of public information has fueled widespread speculation about the case, while investigators have remained largely silent about key questions surrounding Wells' death.

Following the release of the distress call, some people mentioned in the recording were identified online and subjected to harassment, according to their families.

The parents of a 21-year-old man said their son had received threats after false claims circulated online. They said he had boarded the disabled boat only to help and briefly towed it before cooperating fully with investigators by turning over his boat, GPS data and the names of potential witnesses.

His family's attorney said cease-and-desist letters have already been sent over what they described as defamatory allegations.

Crump said his focus remains on uncovering the truth.

"We're not trying to cast aspersions on anybody, we want the truth," he said. "If it was your child, you'd want the same thing."

Crump also appeared alongside the families of Tyler Smith of Kentucky and Daniel Erving of Texas, two other Black 18-year-olds whose deaths remain the subject of disputes with investigators.

"Three 18-year-old Black boys all within three months," Crump said. "We want answers."