"The cause of death is not natural," Her Majesty's Coroner Linda P. Virgill tells PEOPLE. "However, we wish to reserve the cause of death at this time pending the toxicologist examination and report for confirmation of cause of death. Friday is the likely release date for the autopsy and toxicology report."

Daniel Smith was found sitting upright in a chair after going to see his mother and his new half-sister in the private Doctors Hospital in Nassau, Reginald Ferguson, assistant commissioner of the Royal Bahamas Police Force, told reporters late Monday.

According to Virgill, a coroner's inquest with a jury will take place, and Anna Nicole Smith will likely be asked for her testimony. "All persons who are relevant witnesses, like his mother and hospital staff and airline personnel who had contact with him, would have to testify," Virgill says. "The inquest would happen late October or early November to determine how, when and by what manner Daniel came to his death."

She continued, "The family wishes to return the body to the United States, but it won't be released until the reports are in."