In the introduction to the story "Charles" the author gives the reader a great deal of information about Laurie. For one thing the author writes in the voice of Laurie's mother letting us know that he is starting kindergarten about which his mom seems a little apprehensive. It appears that on his first day of kindergarten he decided that he was a "big boy" and no longer needed to wear baby clothes such as overalls.
The reader also finds out that Laurie is not one to cling to his mother because the author writes that he walked off with confidence and attitude to his first day of kindergarten. In fact, the author writes that Laurie barely gave his mom a glance as he went off to school. He must have been close to his mom as she seems surprised that he did not stop to wave good bye.