ABC News received a statement from Jansen Panettiere's family a week after his tragic death at 28.
The coroner attributed Jansen's death to cardiomegaly and aortic valve issues, according to the family.
Hayden Panettiere's publicist, Kasey Kitchen, broke the sad news of her brother's death.
Jansen Panettiere was the actress' only brother. Both began performing as youngsters and were close.
Jansen Panettiere never ceased working for 20 years, although his parts were usually modest or episodic in television programmes.
In "The Walking Dead," he played Casper. It was a one-episode guest appearance. In 2013, he featured on "Major Crimes."
Hayden, his sister, hasn't spoken yet.
"In a city of millions, no one hears you scream," stated the actress's final post before Jansen Panettiere's death. The actress may feel this way after losing her sibling.
Jansen Panettiere's bold, colourful paintings helped him deal with anxiety and melancholy for years. He Instagrammed about it in 2019.
In "The Walking Dead," he played Casper. It was a one-episode guest appearance. In 2013, he featured on "Major Crimes."