Hayden Panettiere and family mourn 'brilliant' Jansen Panettiere, reveal his cause of death

Hayden Panettiere and her family are mourning the sudden death of her younger brother, actor Jansen Panettiere, who died Feb. 19 at age 28.

“It is with great sorrow we share the tremendous, untimely loss of our beautiful Jansen," Hayden Panettiere and the sibling's parents Lesley Vogul and Skip Panettiere said in a statement Monday, shared with USA TODAY by the actress' rep, Kasey Kitchen.

The family revealed the young actor's "sudden passing was due to cardiomegaly (enlarged heart,) coupled with aortic valve complications."

Cardiomegaly has several causes, with high blood pressure among the most common, per Mayo Clinic. Some people experience no signs or symptoms, while others may experience shortness of breath, an irregular heart rhythm or swelling of the belly or legs.

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"Jansen’s heart could be seen in his eyes, and his charm in his brilliant, engaging smile; his soul in his masterful and revealing paintings, and the joy of life in his dry wit," his family continued. "His charisma, warmth, compassion for others, and his creative spirit will live forever in our hearts and in the hearts of all whom he encountered."

Jansen's family members went on to thank fans for "the outpouring of love and support towards our family as we navigate this unthinkable loss," adding that they want to "be gifted our privacy during this time of mourning."

"We love you so much Jansen and you will be in our hearts forever," the statement concluded.

Jansen made his acting debut in 2002 with a voice role in the animated TV series “Midori's Nintendoland Bakery,” which he followed with appearances in the series “Even Stevens,” “Hope & Faith” and “Third Watch.”

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He later co-starred with his sister in the 2004 Disney Channel film “Tiger Cruise,” which was inspired by the events of the Sept. 11 terrorist attacks. They collaborated again for "The Forger" in 2011. His breakout lead role was in Nickelodeon's 2007 movie "The Last Day of Summer."

Jansen rounded out the 2000s with additional voice roles in “Robots,” “Ice Age: The Meltdown” and Nickelodeon’s action comedy “The X’s,” as well as onscreen appearances in 2007’s “The Babysitters,” 2008’s “The Secrets of Jonathan Sperry” and 2009’s “The Perfect Game.”

His last role was in the 2022 romantic comedy “Love and Love Not.”

The 28-year-old was also a painter, often showing his artwork on Instagram.

Contributing: Edward Segarra

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This article originally appeared on USA TODAY: Jansen Panettiere cause of death shared by Hayden Panettiere, family