Between the Line Question: Why does the author always talk about the rabbits?

The author talks about the rabbits because Lennie liked to pet the soft things and just rub them because they felt nice. Later at the end of the book Lennie reveled to Carly's wife that he liked to pet soft things which was why he would always ask George for rabbits. I thought the rabbits symbolizes Lennie being so childish and had a mind of a child