This book helps children know what "being bossy" means and how to tell if they are being bossy. I think that most children can be bossy at one time or another and this book will give you the help you need to point that out to them. I don't think they even know that they are being bossy, most of the time.
(affiliate links are used)
Help Me Be Good - Being Forgetful
Help Me Be Good - Being a Bad Sport
Help Me Be Good - Being Selfish