Dean chuckled, nodding. "Right." And even then, they were themselves. When they were kids, they'd tried to make one another laugh when "undercover" (as long as Dad wasn't around). It was stupid and dangerous, but they were young enough not to care. For some of it, at least.

"You're an all right guy, Dr. Crane." Nothing particular made Dean say it, but it was probably true that the good doctor had made Dean feel a feeling, so he got kind of shmoopy about it and displaced his positive sentimental feelings onto Niles. Or something.