Some great books about new brothers and sisters.
Fine As We Are by Algy Craig Hall is the story of Little Frog and his mom, who live very happily by the pond until all his baby brothers and sisters come along. At first Little Frog finds them annoying and in the way, but he eventually grows to love his bigger family.
Julius, Baby of the World by Kevin Henkes. This is a classic about Henkes’s regular Lilly and her total disgust with her new baby brother. She hates having him around until someone else says mean things about him. Then she becomes a protective big sister and starts to see how special Julius really is.
Sam Lloyd’s Mr. Pusskins and Little Whiskers: Another Love Story is a great follow-up to Mr. Pusskins. When Emily brings home a new kitten, Mr. Pusskins is not happy. At all. But eventually he comes to love the new addition to the family.