They say death comes in threes, which means this past weekend we either got one extra, or there are two more to come. This past weekend we lost four great celebrities.

Shannon Doherty passed away at the age of 53 on July 13 from breast cancer. Doherty rose to fame as Brenda on the hit show 90210, and found a second home as Prue on the television series Charmed. For Gen Xers, Doherty will be remembered either as Rene, Brody’s girlfriend from Kevin Smith’s Mallrats, or as Heather Duke, one of the many Heathers from the 1988 film, Heathers.

Shelley Duvall passed away at the age of 75 from complications of diabetes. Duvall first broke through with her performance in 1977’s Annie Hall, but it was her rolls in The Shining and Popeye, both released in 1980, that made her a superstar. Duvall’s Fairy Tale Theater was a big hit as well. Duvall was instantly recognizable and will be missed.

Richard Simmons, famous workout guru, passed away at the age of 76. In the 1980s, Simmons had seemingly the entire country “sweatin’ to the oldies,” but he was more than just a workout legend — her was a personality. Simmons’ appearances on Late Night with David Letterman, among other talk shows, made him a star. Simmons was known for his generosity and his empathy, often cold calling people to support them in their weight loss journey. In later years Simmons became a recluse, leading to speculation about his health and living situation (check out the excellent podcast Missing Rickard Simmons). Over the past year Simmons squabbled with comedian Pauly Shore, who was been pitching a biopic based on Simmons’ life which will surely now get greenlit.

Dr. Ruth Westheimer, the world’s most famous sex therapist, passed away at the age of 96. Westheimer lived an interesting life. At the age of 10 she was sent from Germany to Switzerland to attend school. Her Jewish parents remained in Germany, and were both killed in concentration camps. At the age of 17 Westheimer joined the military and served as a sniper, only to be discharged at the age of 20 after being injured by an exploding shell while defending Israel in the Palestine War. All of this happened 30 years before Westheimer began her call in radio talk show, Sexually Speaking, in 1980. That show led to multiple television shows and becoming a part of pop culture. Westheimer went on to author 45 books, with another waiting to be published at the time of her death.

Each of these four people contributed to pop culture in their own unique way and will be missed.