In her new book Growing Up Fisher: Musings, Memories and Misadventures, excerpted exclusively in the new issue of PEOPLE, Joely recounts rushing to UCLA Medical Center on the morning of Dec. 23, 2016 to find Carrie in a coma after learning she suffered a heart attack on a plane home to Los Angeles from London.
“Mama Debs was already there,” Joely, 50, writes in the book of Carrie’s mother, Debbie Reynolds. “She told me she had talked to Jesus and prayed for more time, for Carrie, for herself, and for Connie [Stevens — Joely’s mother]. Apparently she had a direct line. It was starting to get very real.”
Joely spent the next few days traveling back and forth to the hospital to visit Carrie and support her family.
“Being in the room with Carrie [it felt] like she was hovering somewhere going, ‘Kids, I’m not sure this is going to work out here,'” Joely tells PEOPLE of her final moments with the star.
On Dec. 27, Carrie died at the age of 60, and Reynolds died just a day later after suffering a stroke. As Joely writes, “Debbie did live for her daughter. She died because she couldn’t be without her.”
Though Carrie’s toxicology report revealed that she had heroin and cocaine in her system at the time of her death, Joely says the family “didn’t attribute it to the struggle with drugs” and that she didn’t “know necessarily that she was struggling at the time.”
“She battled bipolar disorder and addiction her whole life,” Joely explains. “I don’t know that this was any great, significant moment that warranted us all having a discussion about it. I think that it was just the way she carried on her life.”
She adds: “Never would I have imagined that this is how the story would end.”
To read more about Fisher’s story, pick up the latest issue of PEOPLE, on newsstands now.
Though Joely shared father Eddie Fisher with Carrie, who was older by 11 years, and her half brother Todd, she didn’t get to know her siblings until after Star Wars came out in 1977.
“The first time I met my sister — yes, in this family, we got introduced,” Joely jokes. “I knew that I had a sister, and we had a couple encounters when I was a child but very few. [After seeing Carrie play Princess Leia in Star Wars] it made me feel like I could possibly be part princess. It definitely was a watermark for me.”
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While Joely pursued a career in Hollywood like her famous family, she says there was never any competition between her and Carrie. “I think a decade between us really put us in different places in our lives and in our careers,” Joely says. “Clearly, she’s an unparalleled artist.”
Since the devastating losses of Carrie and Debbie, Joely has noticed they’ve taken a toll on her not only emotionally, but physically.
“I look at my face in the mirror, and I feel like starting with my mom [Connie] having a stroke in January 2016 to losing Carrie and Debbie, my mouth has gone down turned,” she says. “I feel like crying and sadness has brought an actual change to the shape of my mouth.”
Despite everything, Joely is focusing on the next generation: the five kids she shares with her husband of nearly 21 years Christopher Duddy, 56 — Skylar Grace, 16, True Harlow, 11, Olivia Luna, 9, and her husband’s two sons from a previous marriage, Cameron and Collin — and of course, Carrie’s daughter Billie Lourd, 25, who she says was “obviously the hardest hit in the family.”
“I think that the best way to celebrate the other people in my family,” Joely says. “Is to go on.”
Growing Up Fisher: Musings, Memories and Misadventures goes on sale Nov. 14.
Watch Joely Fisher and more author interviews on Shelf Life, available Tuesday, November 21 on PeopleTV. Go to PeopleTV.com, or download the PeopleTV app on your favorite mobile or connected TV device.