Hello I am new to this whole chicken hobby I think this little one is a female, but I am not sure. It has "motherly instincts", but I can't assume the sex just because of how it acts or can I? This little one opens up it's legs and then just sits on the other little chicks; like a hen would. I live in the city and can't have roos unfortunately so sexing is important. I think this little one is a gray and not a blue silkie as it has patches of dark black and light gray colors mixed. Here is a picture. Also how old does this chick look? How do I introduce it to the flock? At what age? Thanks in advance.