Matthew McConaughey has written his first children’s book, “Just because.” The book explores all of life's little complexities through the eyes of children while seeing the world and each other as full of possibility. "I didn't make plans to write a children's book so much as the idea of Just Because came to me one night at 2:00 a.m. as a ditty in a dream," McConaughey told People about the picture book. "Hanging around my own children, seeing them first make sense of the world in black and white and then maturing into understanding the more subtle realities of life, I've seen them slowly realize the innuendos, context and poetry in people's actions and feelings," says McConaughey. "I believe this book will resonate with children of all ages 'just because' it speaks to the kid in all of us." The book will be out September 12.