Bobbi Kristina Brown's former boyfriend Nick Gordon died of a heroin overdose.
Autopsy and toxicology reports have confirmed his cardiac arrest was brought on by drug use.
Caffeine, morphine and naloxone, a drug that reverses opioid overdoses, were found in Gordon's system, according to toxicology results, reports CNN.com.
Gordon spent seven hours in the hospital in Florida before he died on 1 January at the age of 30. His brother confirmed the news on New Year's Day, suggesting he'd died after suffering an overdose.
Sources claim Gordon never recovered from the death of his girlfriend, Bobbi Kristina, in January 2015. The daughter of Whitney Houston and Bobby Brown was found unresponsive in a bathtub at the couple's home and she was placed in a coma until her death six months later. Autopsy results declared that drug intoxication and immersion in water were the cause of the pneumonia and brain damage that ultimately led to her death.
Gordon was found legally responsible for her death and was ordered to pay $36 million (£27.8 million) to her estate. No criminal charges were filed.