Figuring out how to build and maintain healthy relationships - with your family, friends, romantically and with yourself - is a crucial part of being a teen. Porn is everywhere, sexting is the norm and messages about body image are highly mixed.

In Doing It, Hannah tackles all of this, everything from masturbation and puberty to slut shaming and consent. How do you know if you have a healthy relationship? Try the Wormtail test. How do you know what's going on 'down there'? Grab a mirror and Hannah will tell you.

Since uploading her first video to YouTube in 2011, Hannah has made over 50 videos talking about sex and relationships and now has this book! Unembarassed and honest, she's the straight-talking big sister you wish you had.

(P) Hachette Children's Group 2017