The late Kim Porter’s friends and family are still mourning over the shocking news of her tragic and sudden death.

Though medical examiners and the Los Angeles coroners still haven’t confirmed the cause of Kim’s death, sources site that Diddy’s ex was suffering from pneumonia in the time leading up to her death.

FYI: The 47-year-old mother of four isn’t the first celebrity to die of this common illness. Others such as Bernie Mac, Stan Lee, Miles Davis, James Brown, and even Harriet Tubman have died from pneumonia.

While some are using her death to advocate for the flu vaccine, others are confused on how people die from the common lung infection. So, why exactly do some people, especially those as young as Kim Porter, die from the flu-like illness, pneumonia? We found out.

Here’s everything you need to know about pneumonia: