Lets cut out the misnomers: Its not a choice. It is, by definition and by demonstration a naturally occurring part of a person's being. It occurs in nature. It occurs in humans. This isn't people choosing to wear blended fabrics or letting their hair or the top of their head show in public. With that addressed, there is no laws preventing ANYONE from entering ANY bathroom they wish without regard for how they are dressed. If you don't want to leave a child unattended in public that's on the parents, who by sheer coincidence are entire measures of magnitude more likely to abuse their own child than any stranger. You shared a unisex bathroom in your home with your parents and siblings, isn't that the real danger here?