(AP Photo/Matt SaylesFans are receiving some closure into John Heard's sudden passing.
E! News can confirm the Home Alone star died in a California hotel room after suffering a heart attack brought on by heart disease.
According to TMZ, who first broke the news, the Santa Clara County Medical Examiner's Office conducted the autopsy and found the 71-year-old died of a "sudden cardiac death due to atherosclerotic and hypertensive heart disease."
Although John underwent a minor back surgery two days before his death, officials say it did not play a role in his passing.
Just last month, E! News reported that the actor was found dead in a Palo Alto, Calif., hotel room on July 21. Soon after the news was revealed, co-stars couldn't help but express their fond memories of the actor.
One of them was Home Alone co-star Daniel Stern who took to social media to pen a touching and lengthy tribute to his longtime friend.
"When I got my first film movie, Breaking Away, the only thing I really knew about film acting was what I had learned from watching John do it," Daniel wrote. "He was as loyal and generous as they come. He was a friend and brother and a legend in his time. RIP John."
Fans may also remember John from his big screen roles in Big and Awakenings as well as his guest TV spots in The Sopranos and CSI Miami.
And if movie and TV roles weren't enough, John also found success in the Broadway community.
He made his Broadway debut in 1973's Warp and would later star in the 1983 revival of Tennessee Williams' The Glass Menagerie where he starred alongside Oscar winner Jessica Tandy.
Our thoughts and prayers continue to go out to his family.