The Roo Who Grew in My Heart is a story that explores surrogacy and associated concepts such as relationships, feelings, and emotions through the experiences of a kangaroo couple, Mr. and Mrs. Roo. Mrs. Roo was born without a pouch and is unable to have a joey on her own. Mr. and Mrs. Roo become Mommy and Daddy Roo with the help of Mommy Kanga, who carries their joey in her pouch. The Roo's become a family through the incredible gift of surrogacy.