Fisher is known best for her role as Princess Leia Organa in Star Wars, played opposite Harrison Ford as Han Solo. Ford isn't one for tweeting but did issue a statement concerning Fisher's health to The Hollywood Reporter.
"I'm shocked and saddened to hear the news about my dear friend," Ford said in the statement. "Our thoughts are with Carrie, her family and friends."
Fisher suffered a heart attack while on a flight from London to Los Angeles. Another flight passenger administered CPR to Fisher. Once the plane landed, Fisher was immediately rushed to a hospital.
Upon arriving at the hospital, Fisher's condition was said to be "not good." Fisher's brother has released periodic updates on his sister's status. Fisher was reportedly stable for a time but has since been moved to the hospital's intensive care unit.
Family, friends and fans alike are offering thoughts, prayers and whatever else they have to offer for Fisher's full recovery.
Ford and Fisher starred in the original Star Wars trilogy together, bringing to life one o of the greatest cinematic romances in all of sci-fi with Han and Leia. Fisher and Ford reprised their roles for Star Wars: The Force Awakens in 2015, which caught up with Han and Leia 30 years laters.