He exhales, a sharp, impressed huff out through his nose, and shakes his head. Even if walking is the slowest possible way to go about it, Daniel can't help but admire the man's resolve. The familial perspective is somewhat beyond his understanding but he'd do the same for any of the members of his team and he has, though maybe not purely by walking.

"Guess it's a pretty important family matter, huh?" Or Nick simply has nowhere else to go, which is a much more sobering thought. The implication that the brothers seem to be involved in some sort of feud or have been avoiding each other for whatever reason probably doesn't help matters.