My own personal example is in the book I was in called "Endangered", I had to leave because of the war. But, I wasn't going to leave Otto! He was my only family at the time. My dad was in Miami and my mom was going out to another sanctuary to get her bonobos there.
Literature is important because it will teach you new things to help you with everyday problems.That can also be called a message or a theme.
Theme and message give you lessons to help you with problems and some examples would be don't judge a book by it's cover or be careful what you wish for.