The relationship between George and Lennie is multifaceted, but in chapter three, we see George's paternal side come out. He tries to provide for Lennie. In the previous chapter Slim gave George a puppy. George, on behalf of Lennie, thanks Slim. George also mentions that Lennie may stay out in the barn and sleep there with the puppy. Lennie is like a little boy.
While Slim and George talk, Slim comments that Lennie is an amazing worker. George is filled with pride, as a father would be proud hearing that his son did something well.
George spoke proudly. “Jus’ tell Lennie what to do an’ he’ll do it if it don’t take no figuring. He can’t think of nothing to do himself, but he sure can take orders.”
George also gives the story of how he and Lennie met. After the death of Lennie's aunt, Clara, the two just stuck together. Hence, we see George's paternal side come out again. Towards the end of this conversation, Slim says these words:
“He’s jus’ like a kid, ain’t he?"
“Sure he’s jes’ like a kid. There ain’t no more harm in him than a kid neither, except he’s so strong. I bet he won’t come in here to sleep tonight. He’d sleep right alongside that box in the barn. Well—let ‘im. He ain’t doin’ no harm out there.”
Finally, George defends Lennie, as a friend. He says that Lennie might not be the brightest person, but Lennie is a good man. Here is what George says:
“He’s a nice fella,” said Slim. “Guy don’t need no sense to be a nice fella. Seems to me sometimes it jus’ works the other way around. Take a real smart guy and he ain’t hardly ever a nice fella.”