Hayden Panettiere is "absolutely heartbroken" over the death of her younger brother, Jansen Panettiere, according to a report from Entertainment Tonight. The 28-year-old actor died in New York on Sunday evening (Feb. 19).

A source tells the publication that the two siblings' close relationship was strong throughout Jansen's life.

"She loved her brother unconditionally and the two shared a special bond," the source explains, going on to detail a mental health battle that Jansen shared with those close to him.

"Jansen suffered from mental health issues and art was his therapy and escape. In the past, Jansen was open to family and friends about his struggles. Hayden was always there for him and constantly tried to help Jansen when she could," the source continues.

TMZ was the first to break the news of Jansen's death, reporting that emergency personnel were called to a residence at about 5:30PM on Sunday. No cause of death has since been made public, nor is the case being investigated as foul play.

Jansen's acting career dates back to the early 2000s, with roles in Even Stevens, Blues Clues and more. He and his older sister, who starred in Nashville, have occasionally worked on the same sets. They both had roles in the 2004 Disney Channel original movie Tiger Cruise and the 2005 American sports comedy Racing Stripes. Jansen was tied to multiple new projects at the time of his death.

When not acting, he shared his graffiti-inspired art with his Instagram followers, using a portion of the proceeds from his art sales to benefit Ukraine and its citizens amid the ongoing war in the country. Hayden Panettiere has also worked to raise funds for Ukraine in recent months, and she's got a personal connection to the country, as she shares a seven-year-old daughter with Ukrainian former professional boxer Wladimir Klitschko.

Jansen is survived by Hayden as well as their parents, Skip Panettiere and Lesley Vogel. The family has not yet issued a statement on his death.

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