I just got 4 new chicks last week - 3 ameraucanas and 1 black sex linked chicken. My black girl was really full of energy when I got her, along with the rest. But, she is the smallest. They are about 5-7 days old. This morning I found she had a bit of pasty butt, so I cleaned her up and have been watching her all day. She is not eating, not drinking and sleeping - a lot! What should I do? If it is likely that she will not make it, should I separate her from the other chicks? Any advice? Thanks! Sad mama!