SANTA FE, N.M. — Lois Duncan was perhaps best-known for her pioneering suspense novels that captivated more than one generation of young readers, including “I Know What You Did Last Summer,” which became a movie with a sequel.

But the prolific writer of nearly 50 titles also chronicled her deeply personal, decades-long inquiry into the unsolved killing of her daughter in 1989, an experience that led her to counsel other parents whose children’s homicides went unsolved.

Duncan died Wednesday in Bradenton, Florida, said her husband, Don Arquette. She was 82.

Arquette said he found Duncan collapsed on the kitchen floor at their home at an assisted living community. Duncan had recently indicated she was having trouble walking, he said Thursday.

Titles by Duncan include children’s picture books and the kids adventure “Hotel for Dogs” that became a feature film in 2009 with Emma Roberts and Lisa Kudrow.

Starting in the late 1960s, Duncan wrote more than two dozen suspense novels aimed at young adults, such as “Down a Dark Hall” and “Stranger with My Face,” that would help define a genre.

The daughter of magazine photographers, Duncan grew up in Sarasota, Florida, and began writing professionally when she was still an adolescent for youth magazines, including Seventeen. She moved to Albuquerque in 1962, where she taught magazine writing at the University of New Mexico.

Her most personal writing chronicled the mysterious shooting death of her daughter Kaitlyn Arquette in Albuquerque as the 18-year-old drove home.

Albuquerque police categorized the killing as a random drive-by shooting. Duncan never stopped searching for a motive and the perpetrators, said Pat Caristo, a private investigator who assisted in the effort.

The ordeal was explored in two books, the first published in 1992 and another in 2013. Arquette said the initial title, “Who Killed My Daughter,” captured national attention and was followed by death threats and the couple’s decision to relocate to Florida.

Duncan went on to assist other parents in similar circumstances and helped create a research center for cold-case homicides that evolved into the Resource Center for Victims of Violent Deaths.

Duncan is survived by husband and children Robin Burkin, Kerry Arquette, Brett Arquette and Donald Arquette Jr.