Oscar-winning actor Philip Seymour Hoffman left behind children and a “devastated” girlfriend, Mimi O'Donnell, after his tragic passing on Sunday. The “Capote” star relapsed in May 2013, but he was reportedly found with a syringe in his arm and heroin in his possession.

The star, who is known for his roles in movies like “The Master,” “Doubt” and, most recently, the upcoming “The Hunger Games,” is survived by Cooper, 10, Tallulah, 7, and Willa, 5 -- the three children he had with O’Donnell, a costume designer who was Hoffman’s partner of 15 years.

The family released a statement via Hoffman's publicist, Karen Samfilippo, which was quoted by USA Today: "We are devastated by the loss of our beloved Phil and appreciate the outpouring of love and support we have received from everyone,” the statement read. “This is a tragic and sudden loss and we ask that you respect our privacy during this time of grieving. Please keep Phil in your thoughts and prayers."

According to USA Today, he finished filming his role in “The Hunger Games: Mockingjay, Part I” as Head Gamekeeper Plutarch Heavensbee. The movie is due out in November. He was also set to reprise his role in the second "Mockingjay" movie, which is currently filming.

"He's one of the best actors on the planet," Francis Lawrence, the director of "Catching Fire," told the news outlet in November. "I thought he would be great at it. I just wasn't sure he'd want to do [the film]. But he did."

Many fans of PSH took to Twitter to share their condolences to O’Donnell and their children. Showbiz Spy wrote Hoffman’s lover was inconsolable when she found out about her partner’s tragic death.

A source told the site: “Mimi is inconsolable.” The insider added that while the amazing actor struggled with substance abuse, he was trying to get better after his relapse in May 2013. “He had his problems, but she thought he was on the road to recovery following his recent rehab stint.”

Apparently O’Donnell had recently heard a death hoax about the Oscar winner days before his actual demise. “Mimi already had a tough few days, after the recent hoax that claimed Philip had died,” the source said. “She will have to stay strong for the sake of their kids.”

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