Pam Dawber is still mourning the death of Rebecca Schaeffer, her former “My Sister Sam” co-star.

Dawber, who played Mindy on the classic TV show “Mork and Mindy,” is speaking out about her murder in 1989 by an obsessed fan.

Pam recounts how her heart was pierced by her friend’s tragic demise. Pam, a more experienced actress, met Rebecca while filming the show. The ladies began as co-stars, but they quickly became friends.

The 67-year-old actress took part in a two-hour ABC “20/20” documentary that aired Friday about one of the earliest celebrity stalker cases, which occurred over 30 years ago.

Schaeffer portrayed Patti, the younger sister of Dawber’s character, Sam.

Rebecca regarded Pam as a role model and sought to her for advice, especially because she was new to the industry and needed assistance to get by.

American actress Rebecca Schaeffer.
CBS Photo Archive/Getty Images, FILE

In addition to Schaeffer’s father, former Los Angeles prosecutor Marcia Clark, and other close friends of the late actress also came through for the documentary.

After Schaeffer was placed on the program, Dawber took her under her wing and even asked Schaeffer – who was then a teenager living in New York – to live with her in Los Angeles for a few months, where she resided with her then-boyfriend, actor Mark Harmon, whom she subsequently married.

“We just kind of fell into this sisterly thing,” Dawber said. “’Cause I’d had a sister. My sister passed away when she was 22 and I was 25. And so having another young girl in the house was something I was very comfortable with. It was good for us.”

The lovely actress rose to prominence in the film business quickly, but met her demise in the hands of a deranged fan called Robert Bardo.

AP Photo

Schaeffer was preparing to audition for a role in Francis Ford Coppola’s “The Godfather Part III” when her stalker crossed state lines and shot her in the head at her Los Angeles home.

In its first season, “My Sister Sam” was a sensation, earning Schaeffer a spot on the cover of Seventeen magazine. Dawber and Schaeffer appeared together on the cover of TV Guide, the number one magazine in the United States at the time.

Pam Dawber was famous actress who appeared in “Mork and Mindy” with Robin Williams before acting opposite Rebecca Schaeffer on “My Sister Sam.”
ABC News

Dawber remarked, “I was thrilled that she was getting to really, really enjoy…a big show biz life.”

Pam reported that hearing the news of Rebecca’s death made her feel guilty. She said she was “devastated,” but felt she could have prevented Rebecca’s death at the age of 21.

Schaeffer got “busy living her life and meeting people and having friends,” according to Dawber.

“The one thing we did say to her, though: ‘You never put your real name on your mailbox, Rebecca.’… And she didn’t listen to that,” said Dawber.

Dawber said she “never had my addresses ever on my driver’s license” after her own encounter with a stalker who police suspect was a male who wrote her letters purporting to be a little girl. ” I always had my business manager’s address…so that you can’t be found.”

“It’s like, ‘You’re on a hit show…we’re gonna go on this show for a while. Do not put your last name on that mailbox,’ and she did,” Dawber continued.

According to authorities, the mentally ill man who murdered Rebecca used information obtained from the Department of Motor Vehicles to track her.  Following his conviction and sentencing in court, the California legislature approved the Driver’s Privacy Protection Act, which prohibits the DMV from disclosing private addresses.

Schaeffer initially caught Bardo’s attention in 1986 when she featured in an ad for the show.  He began following the show and recording her previous appearances on television. He also wrote her a lot of fan mail. He was obliged to go from Arizona to the Los Angeles studio where “My Sister Sam” was filmed in the hopes of meeting Schaeffer after getting a response.

On several occasions, he showed up with gifts for her, but he was never able to get past studio security.