my son wants to be a girl

Yesterday at around 4 pm my son decided he was a dog. He kept this up for the rest of the day until bedtime. He crawled on the floor and said Woof Woof and asked to have his ears scratched. We were outside walking on the sidewalk but he insisted he couldn't walk on two feet.  He ate from his plate without using hands and surprisingly managed it quite well. He did not ask to play with his makeshift dress (actually a large scarf) or costume wig.  I wonder if this means Elsa is gone, or if she will come back again with a vengeance. Will have to wait and see.  I find the dog thing annoying, but not so worrisome as i found being a girl. I guess its because i don't really entertain the idea that one day he will decide, as a teen or adult, that he really is a dog.  

My son goes to a school that has a large contingent from an ethnic minority. We sent him there in part because we thought multicultural exposure would be good for him. But I notice in his class that there is a large group of boys from this population, they speak another language between themselves, and he rarely plays with them. Could that be why he suddenly feels less identified with  boys?

We have a youth volunteer program in our area, and every week a group of 4 teenage  boys have been creating a garden for us, together with a couple of residents from our complex.  Really nice, polite boys. They let my son "help" them; gathering rocks, even planting a shoot (is that what its called? plants are so a foreign language to me). He was so proud. "Look how strong I am!" Walking by the next morning he immediately pointed out his handiwork.  "Did you like those big boys?" I asked. I knew the answer was yes. "When you grow up you'll be a very big boy like them." I held my breath, expecting him to say something like "I'm Elsa and Elsa is a girl. " but he didn't, he said yes.  But while i'm so happy with my son finally identifying with other males, he says, "Right only boys can work in the garden, and not girls?" Oy. Can't my son be happy being male, without making it about superiority

So D. drew a picture on the floor (point of pride here: yes, he's allowed to draw on the floor). "Look Mommy, a girl with a penis!" Of course, it looked pretty much the same as all the people he draws- a big round head with a lot of sticks coming out.  So I said "what a funny girl!" hope that was a good response.  This is no different than any other preschool experimenting and wondering about reality, i think and hope but I worry because its an ongoing preoccuppaiton.  Background because this is my first post: My son is 4 and for a few months he's been wanting to wear a makeshift dress, be princess Elsa, and occasionally insist that he has a vagina.   No transtheory bullshit comments will be published.