Actress Sharon Stone wrote in an Instagram post that her sister, Kelly, has been hospitalized with COVID-19. “One of you Non-Mask wearers did this,” said the 62-year-old, adding that her sister has an autoimmune disorder called lupus that affects the organs and increases her risk of infections like the coronavirus.

According to the Lupus Foundation of America, people with the disorder have difficulty fighting off COVID-19 and should be especially careful coming into contact with others. The organization explains that even the medications people take to treat lupus can also limit the body’s ability to respond to infections.

Stone urged people to “Wear a mask! For Yourself and others. Please.” She joined other celebrities like Tom Hanks, Jennifer Aniston, Morgan Freeman and Reese Witherspoon who have publicly advocated safety measures, according to USA Today.

Kelly said both she and her husband, Bruce Singer, “thought COVID wouldn’t and couldn’t find us,” explaining that the couple seldom ventured out socially and “barely saw a human.”

“Now I’m fighting for a breath,” she said, according to USA Today. “You don’t want COVID.”