Books like The Berenstain Bears No Girls Allowed

My parents often read this book to me when I was a child, probably because I had a younger sister who would tag along when I visited friends... even when I sometimes wished she wouldn't. As an adult reading the book to my own son, I regret that the target of the lesson is not more clear. The title and cover suggest that Brother Bear should be more patient with his sister. However, Mama Bear's lectures and the book's resolution put the blame on sister for not being a more agreeable companion. Maybe both lessons are apt, or maybe the book would make more sense with a new title: "The Berenstain Bears and the Sore Loser."