*adopts an overtly talking to a child tone*
So, when a parent and another parent "make love", one piece of DNA and another piece of DNA come together, but what happens after is very complicated.
While most people with XX chromosomes and most people with XY chromosomes grow up to be girls and boys, respectively, it's not guaranteed.
You see, somewhere during the pregnancy, the mother's body is set up to release a hormone that makes a penis grow instead of a vagina. But this is entirely different from the process that causes a "boy brain" to grow instead of a "girl brain". This means that an XX person can grow up with a penis and testicles and a boy brain, with a vagina and ovaries and a boy brain, with a vagina and testicles and a boy brain, with a penis and testicles and a boy brain, with a penis and ovaries and a girl brain, with a vagina and ovaries and a girl brain, with penis and testicles and a girl brain, with penis and ovaries and a girl brain, with penis and testicles and a girl brain, or a vagina and testicles and a girl brain, *or any halfway state between any of the combinations listed. Same holds true for XY.
In fact, the boy/girl brain is still too granular, as someone can end up with some combination or mashup of individual brain structures.
It's easier to reconfigure the flesh of the genitals and hormones the body is exposed to than it is to reconfigure a brain. So we take the path of least resistance to make people as comfortable in their lives as we may.
This is the reality your god, if he exists, created. To deny it is the highest blasphemy possible, to deny the direct and living word of God, the spoken universe that is creation itself.
Get yourself right if you believe in and fear God, fool.