In the novel The Outsiders how is Johnny in the beginning of the book?

S.E. Hinton's classic The Outsiders is told from the point of view of Ponyboy Curtis. Johnny Cade is his best friend. They are both Greasers. 
Chapter 1 contains a hint as to what happened to Johnny; he was jumped by a bunch of Socs. Ponyboy is bleeding because he was cut by a Soc carrying a blade. Darry and Sodapop, his brothers, come to his rescue. Ponyboy compares his experience to an earlier one that Johnny had: 

You just don't cry in front of Darry. Not unless you're hurt like Johnny had been that day we found him in a vacant lot. Compared to Johnny, I wasn't hurt at all.

Johnny is described as being the gang's pet. He's one of the smallest people in the gang. He's nervous and suspicious not just because of the beating that was alluded to, but also because of his home life.

His father was always beating him up, and his mother ignored him, except when she was hacked off at something, and then you could hear her yelling at him clear down at our house. I think he hated that worse than getting whipped. He would have run away a million times if we hadn't been there. If it hadn't been for the gang, Johnny would never have known what love and affection are.

Johnny is also sensitive and doesn't conduct himself the same way that other members of the gang do. He likes to watch the stars with Ponyboy. Cherry and her friend don't judge him harshly like they do Dally, they can see that he is different, and not a threat to them.