When Marlo Mack's three year old says these words, she's not surprised - but she's completely unprepared.

Marlo gave birth to a beautiful baby boy - M - and brushed his pleas for pink clothes and dresses aside as a young child's playful experimentation with gender. But when her son begs to be put back in her tummy because he came out wrong, she knows she must listen more closely. How to Be a Girl is a raw and unflinching memoir of a mother grappling with her child's transition.

Always wanting to support M, Marlo - whose podcast of the same name has over 1.3 million downloads - finds her liberal values surprisingly challenged, and as she learns more about gender and its varied expressions, she questions what being a girl - or a boy, or something else entirely - really means.