"A couple of weeks ago, my brother Curtis passed away after a life-long battle with mental illness and addiction," Carl wrote on Instagram, adding that losing his "big brother is something I never could have imagined, and the sense of loss is even greater."
But it seems like Carl wants some hope to come from his brother's fate — and that's spreading awareness about mental health struggles and addiction.
In the same post, Carol wrote, "As I reflect on Curtis’ legacy, I think of his huge heart and passion for life. I know he would want to transform tragedy into something uplifting. I’m making it my mission to bring some light to one of the darkest experiences I’ve ever faced… and contributing something in my brother’s honor."
Carl then announced that he was launching a new company called More Summer Fun, which "all about maintaining warm vibes even during the 'stormy' seasons."
He ended his post by writing, "Weathering the storm is far easier when you're surrounded by warm energy and good people. So let's act like it, beach. Here's to transforming a year with lots of loss into something meaningful. More Curtis, More Life."
What exactly happened to Carl from 'Summer House's' brother?
It's only known that 40-year-old Curtis Radke passed away as a result of his struggles with mental health and addiction — Carl hasn't elaborated more on Curtis's condition or whether or not he used drugs or drank alcohol. Some reports confirm that it was ultimately an overdose.
Carl opened up about what it was like growing up with his brother, and admitted that it was sometimes hard to be close with someone who had what sounds like personal demons.
"Loving someone with an addiction is extremely tough. For a long time, I felt a lot of fear and shame about my brother because of the stigma that remains around mental health and addiction," Carl told TODAY. He also shared that when they were young adults, Curtis had sadly dropped out of college, and that he addictions grew worse.
It's unclear how it all started (and mental health and addiction is incredibly complex, so it's difficult to boil it down to a "start date") but Carl did share that Curtis had it rough in high school. They both grew up in a competitive environment, and this seemed to take a toll on Curtis.
"Things changed in high school. We have a very competitive community with sports and academics, and I always felt like we were measured by social status. That pressure was a lot for a 14-year-old entering high school. I think when you're young and don't feel like you fit in, it's easier to run with a crowd who may not be the best to surround yourself with. We definitely noticed a big change in his school work and he found himself getting into trouble a lot more," Carl shared.
Watch Summer House every Thursday at 9 p.m. on Bravo.
If you or someone you know is struggling with alcohol or drug abuse, call SAMHSA’s National Helpline at 1-800-662-4357.