It's pooey on B-A-B-I-E-S until Junie B. finds out that her new dumb old baby brother is a big fat deal. Her two bestest friends are giving her everything they own just to see him. And guess what else? Maybe she can bring him to school on Pet Day. Through a misunderstanding, Junie B. thinks that her new baby brother is really a baby monkey, and her report of this news creates excitement and trouble in her kindergarten class.