Nothing to say is not necessarily a good thing here. Not even Mort tries to interject, which is in and of itself worrying.

But...he remembers leaving Eloe for the first time. Remembers coming across his first caravan, entering a new city. Remembers, despite reassurances, being terrified that the people he met would turn on him for the smallest perceived slight, and being deeply shocked when they didn't. When they treated him like a person instead. When, removed from the context of his past, he could finally be one.

It's not the same for Thanatos, but it's close enough. He lays a hand on Thanatos's arm. "I told you what I needed," he says gently. "You can tell me what you need, and I'll do my best." Wait, that's not everything, is it. "And it's okay if you don't know what that is yet."