M, a handsome baby boy, was born to Marlo Mack. Or so she thought. M began to insist on wearing exclusively pink clothing when she was two years old. M urged his mother to purchase him lovely clothes when he was three and to let his hair grow out long. Friends, family, professionals, and Marlo herself had been able to dismiss these behaviours as a young child's playful gender experimentation, but when her son requests to be placed back inside her womb because he was born incorrectly, she realises she needs to pay closer attention. How to Be a Girl is a raw and unflinching memoir of a mother grappling with her child's transition from male to female. 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.