Reynolds was buried along with some of her daughter's ashes, Ruta Lee, a friend of the "Singin' in the Rain" actress, told ABC News.
The ceremony took place at Forest Lawn Memorial Park in the Hollywood Hills, not far from where Fisher, 60, and Reynolds, 84, lived next door to one another. Fisher's brother Todd Fisher, daughter Billie Lourd, and half-sisters Joely and Tricia Lee Fisher were in attendance, and Lee made a speech and performed an impromptu musical number at the gravesite.
"It was a blessing," she said of being asked to sing.
Carrie Fisher died on Dec. 27, four days after going into cardiac arrest on a flight from London to Los Angeles. One day later, Reynolds suffered a stroke and died.
“She didn’t die of a broken heart,” Todd Fisher told ABC News of his mother. “She just left to be with Carrie. ... Carrie was a force of nature in her own right, you know, it took another force of nature to bridle and work with that and she was great with her.”