Former NHL Player Jimmy Hayes' Official Cause of Death Still Unknown After Autopsy

Jimmy Hayes' official cause of death remains unconfirmed following an autopsy.

A spokesperson for Massachusetts' medical examiner's office confirmed on Wednesday that an autopsy was completed, but the "cause and manner of death remain pending and an update is not expected for several weeks when toxicology testing comes back," read a statement obtained by PEOPLE and The Boston Globe.

Hayes was pronounced dead by first responders at his Milton, Massachusetts, home on Aug. 23. He was 31.

The evening prior to his death, Hayes and his wife of three years Kristen celebrated their son Beau's second birthday with their 3-month-old son Mac, who was born on May 5.

Following her husband's death, Kristen shared heartbreaking words on Instagram Story, writing, "My angel I love you so much. I miss you. I don't know how I'm going to do life without you. You should be here. This isn't fair."

Rocky W. Widner/NHL/Getty Jimmy Hayes

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Kristen also shared that the family of four had taken group photos on Aug. 17, which "little did I know they would be our last photos," she said on Instagram. "I have no words. I'm heartbroken. We miss you. We love you. You should be here."

Hayes, a native of Dorchester, played 334 games over seven years in the NHL for four teams after a successful collegiate career and NCAA championship at Boston College.

In 2008, he was drafted 60th overall by the Toronto Maple Leafs and made his NHL debut with the Chicago Blackhawks in 2011. Two years later he was traded to the Florida Panthers and eventually played for his hometown club Boston Bruins in 2015. Hayes finished his professional career with the New Jersey Devils in 2018.

In his post-NHL career, he was a co-host of the Missin Curfew podcast and his last recorded show was in August.

RELATED: Hockey Player Jimmy Hayes Died One Day After Celebrating His Son's 2nd Birthday

Hayes is survived by his wife Kristen and their two sons as well as his parents Shelagh and Kevin Sr. and siblings Genevieve, Eileen, Justine and Kevin, who plays for the Philadelphia Flyers.

"Yesterday I lost my best friend, my brother. My whole life it has always been Jimmy and Kevin or the Hayes brothers. I have followed you around since I can remember and I wouldn't want it any other way," younger brother Kevin captioned photos and videos on Instagram.

"Whether it was youth hockey, Nobles, Boston College or the NHL, you paved the way for me. You taught me everything I needed to know in order to succeed. You lit up every single room you walked into with your smile and positive attitude. Everyone wanted to be around Jim, the big, goofy, horrible dancer, funny, genuine and kindest person around," Kevin continued. "I will never forget the times we shared or the memories we made and know that I will try my hardest to have your legacy live on. Our world lost someone special and I don't know if I will ever be the same but till we meet again, I LOVE YOU JIM!"

Hayes' first cousin Matthew Tkachuk of the Calgary Flames shared a tribute on Twitter following news of the athlete's death.

"Completely speechless and heartbroken! Wish I had the chance to tell Jimmy how much Brady and I looked up to him and Kevin throughout all the years," Tkachuk wrote. "I know that Beau and Mac will grow up with the same larger than life and loving personality that he had! Rest easy!"