"The only good thing about this is that my mom wanted to be with my sister," Todd Fisher said Wednesday, referring to Carrie Fisher's death a day earlier.
"Thank you to everyone who has embraced the gifts and talents of my beloved and amazing daughter," Reynolds wrote. "I am grateful for your thoughts and prayers that are now guiding her to her next stop. Love Carries Mother."
Reynolds was rushed to a Los Angeles–area hospital on Wednesday, a source close to the actress confirmed to ABC News.
A representative for the Los Angeles Fire Department said earlier Wednesday that authorities responded at 1:02 p.m. Pacific time to a medical aid request on the block where Reynolds has a home. The LAFD transported an adult female in "fair to serious" condition to Cedars-Sinai Medical Center, the representative said.
Todd Fisher told ABC affiliate KABC on Tuesday that family members were coming together to grieve their recent loss.
"My mother is very strong right now, and Billie, Carrie's daughter, is very strong ... We are all together now at this point," he said.
Reynolds coped with her own health issues in the past, including what her son described as "a small stroke" last year.
In May, Carrie Fisher spoke to Entertainment Weekly and People about her mother's health, calling her "frail."
"It's, a lot of times, terrifying watching my mother, who's incredibly resilient, coping with certain health issues that she's had," Fisher said at the time. "[Performing is] the thing that gives her life, but it was also pulling it out of her, because she'd perform and then she'd have to recover. But this is someone who wants to go back and do it now. She became very ill, and now she's bouncing back."