No friends, strange faces everywhere, worries about whether people will like you—that's what it's like being the new kid in school.
We don't meet Barry until Chapter 49, but he's important because he's Leigh's first friend in the new school. When Leigh's lunchbox alarm goes off that first day in the cafeteria, everyone pays attention to him. How could they not with that thing beeping like crazy? But it's Barry who invites him to come over, and it's Barry who turns into a buddy.
We learn that Barry has lots of little sisters, loves putting together models without using the directions, and is totally cool eating over at Leigh's tiny house. In fact, he says he "really liked eating at our house because he got tired of eating with a bunch of little sisters waving spoons" (55.3).
Who hasn't wondered if their house is cool, if they're weird, or if people like them? Barry's acceptance of Leigh, his small house, and his mom go a long way to making Leigh feel less lonely. Leigh's been feeling discouraged and down because of all the changes in his life; it's times like these where having a friend really makes a difference.
When Leigh's dad finally comes around to visit, Barry gracefully exits the scene so father and son can have some private time. Leigh tells us that Barry is someone who has "heard a lot about Dad and Bandit and who understands about parents and divorce" (60.3). This one line says a lot. It tells us that Barry understands that parents have faults and sometimes fight to the point of breaking up the family. It tells us Leigh and Barry have spent enough time together and trust each other enough to tell each other important stuff going on in their lives. Barry understands that Leigh needs some alone time with his dad at this moment.
Pretty solid friend material, wouldn't you say? We suspect that buddy Barry will be around for a while. He's in the sequel, after all.