Jonah Hill's Brother Autopsy Completed; Investigators Looking at 'History of Substance Abuse'

The autopsy of Jonah Hill's brother has been completed, and his official cause of death has been deferred pending toxicology.

Sources close to the death investigation of Jordan Feldstein tell us the autopsy was done on Christmas Eve and the body has been released to the family.

We're told investigators have gathered information from the family that Feldstein did have a history of heart issues, but was not being treated for anything specific at his time of death.

The 40-year-old music manager's family has already released a statement saying his death was caused by a heart attack, but sources tell us there is "no obvious cause of death" at this point.

As we previously reported, Feldstein may have ingested a substance prior to his death, and it's currently being investigated as a possible accident.

We're told the family revealed to officials that Feldstein had a history of substance abuse, which makes the toxicology results that much more important.