When Debbie Reynolds shockingly passed away just a day after her daughter, Carrie Fisher, died, friends and family attributed the sudden death to a broken heart. Reynolds and Fisher weren’t just mother and daughter, they were best friends. Now, the first trailer for the upcoming HBO documentary featuring the two shows just how close they were.

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“Bright Lights: Starring Carrie Fisher and Debbie Reynolds,” co-directed by Alexis Bloom and Fisher Stevens and shot several years ago, premieres Saturday, January 7 on HBO, and if the trailer is any indication, fans of the pair will want to have tons of tissues nearby. Set to an upbeat piano soundtrack, the two minute trailer showcases just how strong the love was between Fisher and Reynolds. Just by watching the trailer, it's evident that the pair not only cared deeply for each other, but relied on each other for nearly everything.

Not only did the mother/daughter team live next door to each other, Fisher even describes herself as her mothers “best friend,” saying she “knows what my mother feels and wants”. The documentary will be centered around the family and their respective careers in Hollywood, the younger star's battles with mental health, and the unbreakable bond between a mother and daughter.

Bright Lights: Starring Carrie Fisher and Debbie Reynolds is an intimate portrait of Hollywood royalty, in all its eccentricity. At 83 years old, grand dame Debbie Reynolds (star of “Singing in the Rain,”) still performs a Las Vegas act, dressed in gold lamé. But performing takes its toll, and Debbie’s health suffers. This devastates her daughter, “Star Wars” actress Carrie Fisher, whose response is both hilarious and heart-rending. Carrie is helpless in the face of her mother’s determination that “the show must go on.”