Speaking for myself, I was not living with any family member at age 14. This was years ago and some of us got disowned and thrown out of our parents home. We had to fend for ourselves. I really think that we should be able to start when ever we are emancipated from our parent's authority. I knew what I was at age 14. I just did not know how to get help.
I have no idea if state laws are applicable. I just assumed that the standards of care for gender dysphoria would apply.