My son is 4 years old and he's showing some signs, but my therapist says it may be too early to tell.
However I'm not really pushing him in that direction, just letting him be.
Signs are:
"I want to go to the girls bathroom" pretty much every time he wants to go (which is often).
Pretending to be female teachers when playing "school" with his sisters
Trying on his sisters' boots and articles of clothing, and putting their bows in his hair.
He even said, "I'm a girl" a few times.
Asks why daddy can wear dresses and he can't. (I've kinda stopped wearing dresses around them now, but I still dress femme).
His mom blames me, says I set a bad example. Obviously she does not know how this works.
I have a cousin who I think is FTM or butch lesbian at the least. He/she hasn't really come out to anyone but is in a committed relationship with a female partner, which he/she pretty much doesn't really tell anyone about, but she (the partner) is there and hangs out with the family and you can tell they are a couple. I am sorry about the pronouns, since my cousin hasn't identified yet I don't know which one to use.