How does Holden describe him parents? His older brother, D.B.? His history teacher, Old Spencer?

Holden describes his parents as touchy.

They're quite touchy about anything like that, especially my father. They're nice and all--I'm not saying that--but they're also touchy as hell.

Holden's brother is a writer in Hollywood. He's got a lot of money, visits Holden regularly, and is a talented writer....... because of this, Holden also calls D.B. a prostitute because he stopped writing for real and started writing simply for the big paycheck.

He's got a lot of dough, now. He didn't use to. He used to be just a regular writer, when he was home. He wrote this terrific book of short stories, The Secret Goldfish, in case you never heard of him. The best one in it was "The Secret Goldfish." It was about this little kid that wouldn't let anybody look at his goldfish because he'd bought it with his own money. It killed me. Now he's out in Hollywood, D.B., being a prostitute.

Holden describes Mr. Spencer as old, stooped, and admirable.

I just mean that I used to think about old Spencer quite a lot, and if you thought about him too much, you wondered what the heck he was still living for. I mean he was all stooped over, and he had very terrible posture, and in class, whenever he dropped a piece of chalk at the blackboard, some guy in the first row always had to get up and pick it up and hand it to him. That's awful, in my opinion. But if you thought about him just enough and not too much, you could figure it out that he wasn't doing too bad for himself.