The teenage son of a pair of prominent Silicon Valley executives died earlier this year due to an accidental drug overdose, the local coroner’s office confirmed to SFGate Wednesday. Marco Troper, a student at the University of California Berkeley and the son of former YouTube CEO Susan Wojcicki and longtime tech executive Dennis Troper, was reportedly found unconscious in his on-campus dorm with a high concentration of alprazolam, an anti-anxiety drug otherwise known as Xanax, in his system, as well as cocaine, amphetamines and a low level of THC. The Alameda County coroner listed his cause of death as “acute combined drug toxicity,” according to SFGate. The coroner’s office report stated that an “abundance” of illicit substances were found at the scene where Troper was found—including Percocet and Oxycodone—though authorities noted that there was no fentanyl found in his system. Neither of his parents responded to a request for comment from SFGate.