My first thought was Boy. I also have little lutino that I THINK is a boy, however after reading that you may have a girl I started to have my doubts about my own little guy. My boy(?) is roughly 5 or 6 years old and has kept his lavender/pink/white cere. He looks just like the description in the link that says what the girls look like. But his behavior, to me, really make me lean to boy still especially around his friend.
Thanks for posting this. I felt kinda sheepish for always assuming that because he didn't have the normal female cere others do he must be a boy.