I have 2 sex links. They had identical markings, then one turned light, with a dusting of red on wings. Oh no, a roo! After about 2 weeks of me giving 'him' the stink eye, the red started filling in over the whole body. So, if you have the right female coloring as a 1 day old, it's safe to say you have a pullet - no matter how they try to tease you!