Mama, something went wrong in your tummy. And it made me come out as a boy instead of a girl. When Marlo Mack hears these words from her three-year-old, she's not surprised - but she's completely unprepared.

How to Be a Girl is a raw and unflinching memoir of a mother grappling with her child's transition from male to female. Marlo wants to support and accept her kid, but she's fearful of the unknown struggles that gender transition might bring. Lack of information on young transgender children and conflicting advice from specialists make the process even more difficult.

Marlo supports her daughter through tricky situations like choosing an inclusive school and deciding whether or not to tell classmates about her transition, and experiences joyful moments as her child makes new friends and meets other transgender kids. As they learn, Marlo becomes part of the fight for trans rights, opposing discriminatory bathroom bills and attending conferences to hear stories from transgender adults and teens who model a possible future for her daughter - one full of hope.