Oscar winner Fisher Stevens witnessed Carrie Fisher's special bond with her mother, Debbie Reynolds, when he directed the documentary, Bright Lights, about the mother-daughter duo.
Stevens recalled that Reynolds was having health issues at the time of filming, which wrapped at the end of 2015. "A large part of the film is that Debbie actually started to get ill," Stevens told Katie Couric on Thursday's Today show. "A lot of the film became about Carrie caring about and caring for her mother."
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Stevens said that Fisher approached him about shooting a documentary about Reynolds' retirement from show business. "Carrie was watching her mother walk down the hill after she just told her that 'I'm going to perform again,'" he noted. "Debbie started filming [the documentary] and she was fine at the beginning, and then it started to happen, her health."
Stevens was stunned to learn that Fisher had died at 60 on Dec. 27, a day before Reynolds' death at 84. "We were quite shocked when Carrie went first, obviously," he said.
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As for what viewers can expect from Bright Lights when it premieres on HBO on Jan. 7, the movie features lots of home video footage and gives an intimate look into Fisher and Reynolds' relationship through the years. "They always sang together," Fisher remembered during his time with the actresses. "They always would just break out into song."
Fisher's brother and Reynolds' son, Todd Fisher, spoke to ET about his mother and sister's closeness. "She missed her daughter and wanted to very much be with her," Todd told ET Reynolds' state of mind during her final hours. "She had been very strong the last several days. [There was] enormous stress on her, obviously. And this morning she said those words to me and 15 minutes later she had a stroke and virtually left."