One Below Deck Mediterranean yachtie is Grayson  Prestongrieving a tragic loss.

During the Bravo series' Sept. 2 episode, season nine Deckhand Nathan Gallager received news that one of his best friends died while he was away at sea—and he was understandly devastated.

"So, I get this text saying that my friend has passed away from cancer," the Ireland native explained in a confessional. "I knew he had cancer, but the night before I came to join the boat, we were out drinking. He wasn't drinking but he seemed okay. Thinking about the memories and things like that, it's a lot of information to gather at once and I'm just pushing that aside for now."

Later, while the entire crew was enjoying a night off by partying together in Greece, Nathan's boatmance partner, fellow Deckhand Gael Cameron, noticed he wasn't quite himself. And on the ride back to the boat, he finally shared the unfortunate news to Gael and Chief Stew Aesha Scott.

Once back at the dock, Nathan finally let his emotions out.

"I don't know why I'm so sensitive but I'm so sad," Nathan confessed to Gael in tears, to which she comforted him by replying, "Who cares if you're sensitive, man? You're going through s--t. It's okay. You're allowed to be sad sometimes."

However, he noted, "It's really f--king hard though. I'm really struggling to cope with it."

In a confessional, Nathan explained why his loved one's passing was particularly overwhelming.

"My mom was going through tests for cancer recently," he shared. "She's been cleared now, thankfully. I found out through my sister. My mom didn't tell me directly. Grief and things like this isn't something we talk about. I definitely tend to push people away. I'm doing what my mom does."

And after Aesha informed Nathan's BFF, fellow Deckhand Joe Bradley, of his grieving, Joe offered him all the support in the world.

"It must be so hard for Nathan to deal with this," Joe reflected in a confessional. "Like, I couldn't remotely imagine. He's a brother to me at this point, so I'm gonna be there for Nathan. Whatever he needs, we'll get done. I want to show him that he's got me."

In the end, the heartbreaking incident actually brought Nathan and Gael closer together.

As she explained in a confessional, "It's definitely a different side of Nathan. He obviously has a very sensitive spot that he doesn't show that often and it just hurts to see him upset. I feel like Nathan was there for me when I was going through a hard time with my ex, and I just want him to know that I'm here for him too."

Below Deck Mediterranean airs Mondays at 9 p.m. on Bravo.

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