The same thing that happened to Cathy Anne's son also happened to my son,Sorry about this being so long.
I have twin 6 year old boy/girl twins, And my daughter was invited to one of friends birthday party that for girls only, and the party was being held at Chucky Cheese (As I have said in my other posts) my son has actually switched places with his sister when we went to a birthday party at a local duckpin (small balls) bowling alley for my nieces son and no one even knew they were wearing each others clothes, I also have a 3 year old son that likes to wear girls clothes, he has also worn girls clothes in public. Both of my sons could be totally dressed in boys clothes and they will be mistaken for girls, Alot of people say that i have 3 pretty daughters and sometimes I will correct them and sometimes I wont.
My daughter was invited to a friends birthday party not too long ago and it was a all girls party, Well my 6 year old son complained to my friends mother also and She said that he could go as long as he was dressed as a girl, (My daughters friends parents have seen my son in girls clothes before and know that he looks just like a girl while wearing them), They also have seen my 3 year old son dressed in girls clothes, They also have a 3 year old daughter.
My daughters friends father of all people said that if my 3 year old wanted to go to the party also he was more then welcome, The father said that he could go either dressed as a boy or a girl. I talked to my 3 year old and he said he wanted to go dressed as a girl just like his brother.
I took all 3 kids (I had my sons dressed in their own clothes) to the store and we were looking at dresses for my daughter when a store clerk came up and asked if she could help, I said that I was looking for a dress for my daughter for a birthday party she was going to, She said that i had 3 very pretty daughters and i said thank you but 2 of them are my sons, She asked which ones and i said to pick out a dress and give it to who she thought was my daughter so she could try it on, I said but if you give it to one of my sons, He is going to try the dress on and i wont let her know until after the dress was tried on, She said ok and she looked at all 3 kids and she picked out a very pretty pink dress that came down between the knees and the ankles and she handed the dress to my 6 year old son, He took the dress and we went into the dressing room to have him put it on, after we went back out to show the store clerk, She said that you look like a very pretty young lady with that dress on, I gave a little nod to let my son know that he could say something to the clerk, and he did, I thought that she would start laughing but she did not, She then asked me if she could try to pick out my daughter again since she had a 50/50 chance, I took my 3 year old son and daughter aside and asked if they were willing to try it again, and i said to my son that the clerk might think that he was my daughter and have him wear a dress, He said he was willing to take that chance, So we went back over to the clerk and she looked at both my daughter and 3 year old son for about 5 minutes, She then went to the little girls dept. and picked out a exact copy of the dress that my 6 year old son was wearing, We did not say anything yet, We went into the dressing room again and i put the dress on my son, when we came out, The clerk said that he looked like a very beautiful princess, Then my son said that he was a boy, I thought that the clerk was going to faint. The clerk could not beleive that my sons could look just like girls in the dresses, I told her that my daughter needed a dress just like her brothers were wearing, after my daughter had her dress, which she put on to make sure that it fit her, All 3 kids took off the dresses and put their own clothes back on and we then went over to the shoe dept. and all 3 kids tried on shoes (black mary janes) and i bought the shoes and dresses and the clerk asked how well we knew my daughters friend and her parents, I said not that well because it was a new friend and the party was going to be held at chucky cheese, The clerk then suggested that all 3 of the kids go dressed as girls and no one would be the wiser.