The 27-year-old's body was found in his car in Connecticut on Wednesday (21Sep16), and he was subsequently pronounced dead at Danbury Hospital in Fairfield County.

Coroners have since revealed he sustained a self-inflicted gunshot wound to the torso and they have ruled his death a suicide, a representative from the Connecticut Office of Chief Medical Examiner confirms to

Mia adopted Thaddeus, who was paraplegic due to polio, in 1994 from Calcutta, India. He was one of 10 children the Rosemary's Baby star has adopted.

She broke her silence about Thaddeus' death with a post on Twitter on Thursday (22Sep16), when she asked fans to lend their support to the American Foundation for Suicide Prevention.

Her Twitter statement reads: "We're devastated by the loss of Thaddeus, our beloved son and brother. He was a wonderful, courageous person who overcame so much hardship in his short life. We miss him.

"Thank you for the outpouring of condolences and words of kindness. If you or someone you love needs help, or if you want to support a group doing life saving work, please visit:"