When Ben puts on his dress blues, he doesn't look like a kid and he doesn't look like a cop; he looks like an ideal.
John feels a swell of pride that is, maybe, unjustified, Ben would be a good cop no matter who his training officer was. He's a good man (no matter who his father is).
Ben catches him staring from across the room. He doesn't smile or smirk, but his face relaxes in that way he has when they're alone together on John's couch, in John's home.
Yeah, John thinks, this is good.
Hang on to this.