Much as I try my best to respect people's orientation, this is just too early. I know kids who tend to show this tendencies even from a young age but I don't think you should allow them to go full drag, not yet. Just affirm to them that they'd be loved whatever they are but also make it clear that there's a time for that later and being dependents, you expect them to act the way you expect them to. Just tell them to go full drag, butch, attack helicopter, whatever in college.
I don't see how this can possibly be a good thing, I think that people should be able to label themselves however they want and live whatever life they want but when they try to "teach" it to a young mind I think that crosses the line. Some of those kids look like they are in diapers, I can't see them knowing at 3 years old they are born a boy but want to dress up like a girl unless it is taught to them
You'd be surprised at what kids would do if you allow them their way. I've seen little boys try on their mothers make up, even when they are repeatedly scolded not to do it again. That don't automatically make them gay though, that's too young an age to even think of sexuality, IMHO.