I just think these parents are setting this child up for an absolutely horrible childhood, and it's a true shame. When you are in first grade, you should be (as one commenter stated), "blissfully ignorant" of a lot of that stuff. And I honestly wonder what the parents mean when they state the child "expresses herself as a girl".
I know plenty of heterosexual men that played with dolls when they were younger (or engaged in other traditional female stuff), and I know plenty of heterosexual women that played with GI Joes or whatever else at the time. These parents just strike me as the obnoxious type that would pounce on anything like that and say "OUR YOUNG CHILD WITH MALE GENITALIA IS TRULY A WOMAN INSIDE, AND YOU BETTER RESPECT AND ACCOMMODATE HIS LIFESTYLE DAMMIT!"
Not to mention, they are the type of parents that would take even the most innocent of behaviors (like I listed above) and immediately start perpetuating to their child that he is different and should embrace his new-found gender identity.