George Milton and Lennie Small are an unlikely pair, but they always travel together in Of Mice and Men by John Steinbeck. While this is a really good thing for Lennie, a mentally challenged giant of a man, it is certainly an inconvenience for George, a small, spare man. Quickly we learn the reason for this is that Lennie gets himself in trouble everywhere they go.
The men are itinerant ranchers who had to leave their last job in Weed because Lennie has an innocent but annoying obsession with petting soft things. When he tried to "pet" a woman's dress, she got frightened and the men had to leave. Now they are on their way to a new job, and George has to make sure Lennie understands that there can be no screw-ups this time. He tells Lennie to keep quiet and let him do all the talking.
In chapter three of the novella, when they arrive at their new ranch, that's kind of how it goes; however, the boss is a little concerned that George is taking advantage of Lennie by making him work and then stealing his money. When the boss asks George directly about it, this is the explanation George gives:
"He's my.... Cousin. I told his old lady I'd take care of him. He got kicked in the head by a horse when he was a kid, He's awright. Just ain't bright. But he can do anything you tell him. "
We learn something more about their pasts later, but this is George's public story.
It is interesting to note, however, that while traveling with Lennie is often inconvenient for George, he does appreciate the companionship. Theirs is a lonely and detached kind of life, moving from place to place without putting down any roots or developing close relationships. Earlier in the story, Lennie eagerly asks George to again tell him about the dream and plans the men have for their future.
While other men drift from place to place and have no one or nothing to call their own and no prospects for a satisfying future, George and Lennie are different.
"With us it ain't like that. We got a future. We got somebody to talk to that gives a damn about us. We don't have to sit in no bar room blowin' our jack jus' because we got no place else to go. If them other guys gets in jail they can rot for all anybody gives a damn. But not us. " Lennie broke in. "But not us! An' why? Because .... Because I got you to look after me, and you got me to look after you, and that's why. "
Obviously there are some negative aspects of traveling with Lennie, but it is clear that George does appreciate having someone to travel with in a world where most people like him have no one. Lennie, of course, could not survive on his own, so he is blessed to have someone like George to look after him.