This is devastating.

Nico Scholly — star of Bravo reality series Below Deck — revealed on social media that his brother Tristen died at age 21. The cause of death has not been disclosed.

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Nico also shared this photo of the boys on his Instagram account.

"My best friend. My other half. My favorite little s–t. I hated you quite often but loved the hell out of you no matter what. My heart is completely broken. This strong and amazing young man will be donating his heart, lungs, and organs to save peoples' lives. I'm going to miss you so much Tristen. You're to young to say goodbye so I'll see you again brother," he captioned the image.

Our thoughts are with Tristen's loved ones in the wake of this tragedy.