One of Britain’s most famous transgender personalities is swapping genders for the third time in eight years. Brad Cooper became the U.K.’s youngest person to undergo a gender swap at only 15 years old, when he claimed he believed he was a girl stuck in a boy’s body. Doctors began pumping Brad’s body full of hormone therapy to stop puberty and trigger breast growth, sparking a widespread debate on whether 15 was too young for a person to make such a life-altering medical decision. Turns out that it just might be. According to a profile in the U.K. Mirror, the...