Our children are struggling to know how to live in today's world. Unprecedented numbers are being diagnosed with mental health disorders, medicated, or are facing a crisis of identity. For almost 100 years the Tavistock and Portman has been at the forefront of exploring young minds. This series, with exclusive access to the Trust, goes behind Tavistock's doors for the first time. It's the first question that's asked, before we're even born - 'is it a boy or girl?' But for an increasing number of children, the answer isn't straightforward. The first programme in this series, directed by Bafta-award-winning Peter Beard, follows two families who attend the Tavistock's Gender Identity Development Service, through life-changing decisions.