These three chicks are all supposed to be black sex links (BR mom/RIR dad, but brooded by a black sumatra). They all have white dots on their heads and I know that is supposed to be an auto sexing feature, but one chick is not like the others. The others are developing cones that are already turning red. They also have solid black faces. The third chick has a cream colored face and no cone development. It's barring pattern also seemes to be different from the other two. Could it be a hen?