It is believed she was planning Carrie’s funeral with her son Todd Fisher when she fell ill.
It was reported someone at his home in Beverly Hills, California, called 911 shortly after at 1.00pm local time.
She was then rushed to a Los Angeles hospital, with E! News reporting that she was in a “fair to serious condition”.
Reynolds was a famous actress in her own right and played iconic roles in Tammy and the Bachelor and The Unsinkable Molly Brown, for which she earned an Oscar nomination.
Her death comes just one day after her daughter passed away
Debbie was rushed to hospital following a stroke on Wednesday
The Hollywood legend received the Screen Actors Guild lifetime achievement award in January 2015 for her work in the film industry.
Her relationship with her daughter was the focus of Carrie’s semi-autobiographical book Postcards from the Edge, which was adapted into a film starring Meryl Streep and Shirley MacLaine.
Reynolds famously divorce Eddie Fisher in 1959 after his affair with Elizabeth Taylor and went on to marry two more times.
She is survived by her son Todd, who told Variety: “She wanted to be with Carrie.”
The Hollywood legend is known for her role in Singin’ in the Rain
Tributes to Reynolds have already begun pouring in, with Joan Collins tweeting: “Truly heartbroken to hear @DebbieReynolds has died. She was a wonderfully warm friend and colleague. Praying for Todd & Billie. #RIPDebbie.”
Frankie Grande added: “My heart is breaking over Debbie Reynolds and I am sending all my light and strength to Billie Lourd.”
US chat show host Ellen DeGeneres shared: “I can’t imagine what Carrie Fisher and Debbie Reynolds’ family are going through this week. I send all of my love.”
Singer Alexandra Burke tweeted: “Finding it so hard to watch the news. Can’t believe Carrie fisher and her mother Debbie Reynolds have passed away.. tragic. So sad…”