The tribute at Forest Lawn Cemetery, where the pair are buried together, was put together by the Star Wars actress' brother (and Reynolds' surviving child) Todd Fisher.
The memorial began with a military color guard for the Singin' in the Rain star, who had performed for the troops over the years, even making several trips to those serving in Korea in the 1950s.
Todd then recounted a story about being with his mom as a kid when they encountered a fan: "Not one fan I ever saw her turn away." It was a lesson she drilled into her kids and one that Carrie practiced when she found fame at the age of 19 as Princess Leia.
"[Carrie] was always my princess," Todd added. "These were my girls."
Todd explained that his mom had previously said that she didn't want to outlive her daughter, who had battled drug addiction and mental illness over the years.
After Carrie died, Reynolds looked at her son "and asked permission to leave," Todd told the audience. "She closed her eyes and went to sleep. ... It was a very peaceful exit that only my mother could have orchestrated. She was trained in Hollywood, where they teach you to make a great entrance and a great exit."
There were several poignant moments during the service, including one that came after a video of Carrie in Star Wars was shown. Robot R2D2 came out onto the stage looking for his princess, making plaintive noises before rolling over to an empty chair.
The memorial also included some of the last footage ever shot of Reynolds, showing her talking about her heartbreaking meetings with injured soldiers in Korea, about the Thalians charity that she founded to help those with mental health issues and about her love for dance.
"Happiness, that's what dance is all about," Reynolds said in the clip. "I've dedicated my life to sharing this joy with the world through Debbie Reynolds Dance Studio."
The video was followed by performances featuring dancers of all ages from the studio.
Other performers included the Gay Men's Chorus of Los Angeles, and Reynolds' close friend and Seven Brides for Seven Brothers star, Ruta Lee.
TCM's Ben Mankiewicz spoke, as did Carrie's friend Griffin Dunne and Carrie's former fiancé and Blues Brothers costar Dan Ackroyd, who lightheartedly related how she sought his advice during their engagement about reconciling with her future husband Paul Simon.
James Blunt was a close friend of Carrie's and, while he wasn't in attendance, his hit "You're Beautiful" played over a montage of pictures of the Wishful Drinking author. "He wrote the song in Carrie's bathroom, on the piano in there," Todd revealed. "He loved Carrie very much. The British singer wrote a tribute song for Carrie that was played later during the service.
Carrie's daughter, Billie Lourd, was in attendance, as was her beloved therapy dog, Gary, along with Carrie and Todd's half-sisters, Joely and Tricia Fisher, and their mom, Connie Stevens (who was married to the late Eddie Fisher in the 1960s).
Todd also shared plans for a permanent tribute to his mom and sister, and revealed that he is planning to include rooms from the pair's adjoining L.A. homes — Carrie's writing room and Reynolds' bedroom — in the museum. "It's where they held court," he explained.
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