Sex and gender mean the same thing.
One’s gender is determined by chromosomes.
Additional variables are the development of reproductive organs and the production of gametes (sperm or eggs). These biological factors align with the biological understanding of male and female.
In other words, when a mother gives birth and the doctor congratulates her on a bouncing baby boy, it’s because he saw his little penis. This practise has occurred throughout history and has been very reliable.
There are exceptions, such as hermaphrodites (who produce both male and female gametes), but they’re rare.
Transgenderism is a slippery slope to dangerous outcomes. Firstly, there is no such thing as a “transgender” individual. A man can’t become a woman and a woman can’t become a man.
Secondly, medical interventions for “transgender” individuals, such as hormone replacement therapy (HRT) and gender-affirming surgeries are little more than self-mutilation, as stated by Walt Heyer (who regretted trying to become a woman).
Such interventions have health risks and long-term psychological consequences because they are unnatural and somewhat transhumanist.
