Martin Short’s late daughter, Katherine, was friendly but mostly kept to herself, according to her neighbors.

Katherine died by apparent suicide on Monday. She was reportedly found dead with a self-inflicted gunshot wound at her Hollywood Hills, Calif., home, per TMZ.

The social worker’s next door neighbor described her as a “great neighbor and gardener” to Us Weekly, and called her death “incredibly sad.”

Another neighbor noted that Katherine was “very nice,” and didn’t throw loud parties and largely kept to herself.

A third neighbor shared with the outlet that while Katherine seemed friendly, and would wave “hi” while sitting on her porch occasionally, they didn’t interact very many times.

Short’s rep confirmed Katherine’s heartbreaking death to Page Six on Tuesday.

She was 42 years old.

“It is with profound grief that we confirm the passing of Katherine Hartley Short,” the statement read.

“The Short family is devastated by this loss, and asks for privacy at this time. Katherine was beloved by all and will be remembered for the light and joy she brought into the world.”

Katherine was the eldest child of the “Only Murders in the Building” star and his late wife, Nancy Dolman. Dolman died in August 2010 after a battle with ovarian cancer.

The couple adopted three children before Dolman’s death — Katherine, as well as sons Oliver, 39, and Henry, 36.

Although Katherine largely remained private, she did attend a handful of public events over the years, posing for red carpet pics alongside her parents.

She was educated, graduating with her bachelor’s degree in psychology and gender sexuality studies from New York University in 2006, and later earning her master’s degree in social work from the University of Southern California in 2010.

She was also involved with Bring Change 2 Mind, a charity that strives to reduce the stigma surrounding mental health.

If you or someone you know is affected by any of the issues raised in this story, call or text the Suicide & Crisis Lifeline at 988.