Welcome to Harry Potter and the case of the teenage depression.    The popular series is being used in a book designed to help teenagers deal with feelings such as anger and depression.     Australian psychologist  Dr Julie-Anne Sykley has written the book Harry Potter Power , which uses ideas and characters from British author J.K. Rowling's series to help teenagers develop a happy feeling.    Ms Sykley said she had been working on the book for 10 years to help young people feel happier , healthier and more powerful.     "I found there was a lot of special hidden material in the (Harry Potter) books and lots of powerful psychological messages that could help young people," she said .    " I sense  _ really need some help and guidance to improve their resilience and help them make better choices in their life ." Harry Potter fans would be familiar with characters in Ms Sykley's book.  " The magical hippogriff creature , for example , was used as a symbol of hope in Harry Potter Power," she said .  Dementors were depressing spirits used in her book to help teenagers learn how to prevent mental illness , Ms Sykley said .  "It's a great way to introduce the idea of depression ," she said .  " Puzzles, games and secret messages were designed to keep learning about depression and anger interesting and informative," she said .  Although Harry Potter Power was marketed to young people aged 12 and older , Ms Sykley said it was suitable for adults and professionals such as teachers and psychologists. Many Harry Potter fans have welcomed the book , which is published by Interactive Publications , and is now on sale . What's the purpose of Ms Sykley's book ?
To explain why young people like Harry Potter. To help teenagers with their mental health problems. To let more readers know about the Harry Potter series. To discuss whether J. K. Rowling's works are suitable for parents.