Patrick Dempsey paid tribute to Amanda Peterson, his co-star in "Can't Buy Me Love," via a touching message on Twitter on Tuesday.
"In my memory, she will always be vibrant and young," Dempsey wrote. "Gone too soon. Sending my thoughts and prayers to Amanda's family."
Sgt. Mike Moran from the Greeley Colorado, police department confirmed that Peterson was found dead at an apartment complex Sunday. She was 43.
No cause of death was given. Her death is still being investigated.
"Amanda was in very good spirits," Peterson's mother, Sylvia, told "Entertainment Tonight" about meeting with her daughter last Wednesday. "This was not, in any way, a drug thing," she added.
Peterson is survived by second husband David Hartley and two children.
Peterson played cheerleader Cindy Mancini in the 1987 romantic comedy "Can't Buy Me Love." She's been away from the entertainment industry for years; her last film, "Windrunner," came out in 1994.