Charlbi Dean's Brother Shares Details About the 'Caring' Actress's 'Shocking' Death at Age 32

"She was really the glue that kept us together," Alex Jacobs said of sister Charlbi Dean's role in his life, after her recent sudden death at age 32

After Charlbi Dean's death at age 32, her brother is remembering the actress as "extremely caring and extremely loving, more than anyone I could have ever known."

On Wednesday, Alex Jacobs told Rolling Stone that his sister's sudden death in New York City on Monday happened after she began experiencing "minor" symptoms and soon asked her fiancé, Luke Volker, to take her to an emergency room. She died just hours later.

"This happened literally within the span of a day: getting a headache, going to sleep, waking up her boyfriend and saying please take me to the hospital," Jacobs, 21, told Rolling Stone.

"We still aren't entirely sure [what happened]," Jacobs added. "There's an autopsy being done which we know might take quite a while. But what we have heard [that] there was a viral infection in her lungs."

Jacobs told Rolling Stone that Dean was involved in a "very, very bad car accident" around 2009, after which doctors removed her spleen. She also suffered broken ribs and a broken back in the accident, according to her brother.

"[The spleen is] involved in fighting off infections, and that could have had something to do what happened," Jacobs said. "Her spleen not being there just added on to the reason why she perhaps couldn't fight it off."

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

Charlbi Dean. Samir Hussein/WireImage

On Tuesday, PEOPLE confirmed that Dean died of an unspecified illness. The a South African-born actress stars in the upcoming film Triangle of Sadness, which won the Cannes Film Festival's highest honor, the Palme d'Or, earlier this year.

"She was extremely caring and extremely loving, more than anyone I could have ever known," Jacobs told Rolling Stone. "She reminded us every day how much she loved us."

"This is quite shocking for us right now, having something like that happen. She was really the glue that kept us together," he said.

Jacobs told Rolling Stone that he is worried about Dean's fiancé, 26-year-old Volker, in the wake of her death, saying that he and the rest of Dean's family "love him so much."

"I can't imagine what it would have been like, being there," Jacobs said. "My mom's biggest worry was that she was going to die alone. He was with her, as close as he could be."

Charlbi Dean. Lionel Hahn/Getty

On Wednesday, Volker, a model/artist, shared a brief video on his Instagram to show appreciation for messages he received after the death of Dean, who was also known for roles in the 2010 South African film Spud and the superhero CW series Black Lightning.

"Hi, everyone. I wanted to just post a picture of Charlbi, but it's a bit hard," began Volker. "And just wanted to let you know I see all your messages, all the love, and I appreciate it. I really do. It's just I can't really reply to them right now. But thank you, guys. I appreciate it. I love you."

In an April 8 Instagram post, Dean revealed that she and Volker got engaged in New York City. She wrote alongside photos from the proposal, which happened at the spot where they shared their first kiss.

When she had her breakout performance in Triangle of Sadness, Volker expressed how proud he was of Dean on social media in May.

"3 years later!!" he wrote in an Instagram post. "Against all odds, almost impossible obstacles, they pulled it off! The film is a masterpiece from top to bottom everyone did a spectacularly job getting it done. I couldn't be more proud of you my love."