David Boreanaz shocked by death of Chad Lowe's teenage daughter

David Boreanaz has shared his grief after the death of his close friend Chad Lowe and wife Kim Painter's teenage daughter.

The couple's daughter, Fiona, 13, was pronounced dead shortly after 1 am local time on Tuesday. Her death was ruled a suicide by the coroner's office.

Mourning her and offering support to her parents on Thursday, the Buffy the Vampire Slayer alumni wrote on Instagram: "My deepest condolences to my friends Chad and Kim with the loss of their beautiful soul, Fiona."

Alongside a photo of Boreanaz and Painter with their respective children, the Angel star continued, "May she be surrounded in light and dance in heaven with all the angels. If you or someone you know is experiencing such difficulties, you can contact the lifeline by calling or texting 988."

Painter responded in the comments, "Love you so much @imdboreanaz - we all do."

Announcing their daughter's death on Tuesday, Painter and Lowe said in a statement, "We are deeply heartbroken by the loss of our beloved Fiona."

The couple, who have two other daughters, described Fiona as "a loving young girl who was smart, creative, and loved to dance".

They added, "She was adored by her sisters and she was deeply loved by her parents. In fact, she was the light of our lives. Her passing is devastating for our entire family and we ask for prayers and privacy at this time."

Chad, the younger brother of actor Rob Lowe, and Painter wed in 2010. He was previously married to two-time Oscar winner Hilary Swank from 1997 to 2007.