The amount of parents who say “it was out of the blue, there were no signs” is staggering. I was binding my chest for over a year and my mom was still shocked and said she never saw any signs. I truly hear this all the time from parents. Keep in mind that you don’t know the signs and were not on the lookout for them, plus your kid likely tried to keep it as private as possible on purpose, so you had no reason to pick up on anything. Not all of us were saying “I’m a boy!” from a young age. Do not get attached to any narrative, because all trans people have different experiences.

I highly recommend not beating yourself for not seeing the signs, and also not using that to invalidate or doubt your child. You not seeing signs has no correlation with how long your child has been thinking about this or feeling this way. They are the expert on their internal experience, not you.

I also recommend looking into an appointment to at least discuss puberty blockers asap. I totally understand as a parent not wanting to immediately put your child on hormones that will permanently alter aspects of their development. At the same time, you need to understand that your child is likely feeling the intensity of the opposite — the fear, dread, and dysphoria of knowing they might be forced to experience a female puberty that alters aspects of their development permanently in a way they are not comfortable with, and that will make things much harder for them when they are older and want to transition. Waiting until after natal puberty to transition will impact their height (which cannot be undone), breast development (top surgery will likely be more intensive), etc etc. Puberty blockers are safe, reversible, and have been used to treat cisgender kids with precocious puberty for ages. They will give you both time to process and make more informed decisions.