Caitlyn Jenner, has been Caitlyn her whole life. "Bruce" was merely a mirage of sorts. Now, first of all I wish that you addressed the question without using "Bruce", but we can t change that now. Anyways, people who are transgender are uncomfortable in their body, until it is changed to their liking. Majority suffer from dysphoria when they don t feel like they are passing, someone disrespects them, etc. Dysphoria still lurks obviously until you transition (if you choose to, some people may not). Now, gender is what you identity as, and there are a number of things (male, female, demigender, agender, bigender, genderneutral, etc.), while sex refers to the genitals you were born with, BUT let me tell you this - if you have a penis and Identify as a women, then you have female sex organs. If you have a vagina and identify as male, you have male sex organs. Support Caitlyn and be respectful. It was her choice to transition, but it was not her choice to feel this way. She has been a women all her life. She s wonderful, gorgeous, and amazing.