I bought an older Polish hen about 5-6 months ago (I've always wanted a Polish, but couldn't locate hens near my area). Anyway, her age is unknown...maybe 5 or 6 years old. She was laying eggs every 2-3 days, but I noticed in the first few weeks of having her that she was pretty darn clumsy. I looked at her eyes and noticed the pupils had a gray hue to them and pin points of white in the center of it. It seems to be getting progressively worse and I worry now about Mareks after reading about it. This leads to an additional question. Observations of my hen: 1) gray pupils with a pinpoint of white in the center 2) not very active, possibly due to having difficulty seeing 3) always has a bald spot the size of a quarter on her head which constantly gets ingrown feathers (previous owner said she had it for years, thought maybe rooster was pulling feather out) 4) she recently did produce fertile eggs...babies are about 6 weeks old and healthy, but I haven't vaccinated them for Mareks yet and they chicks have been around her since birth (I let one of my broody Buff Orpingtons sit, hatch, and raise them.) Question: Should I be concerned? Or does this sort of thing happen to Polish hens due to the feathers against the eyes? Question 2: Can I still vaccinate the 6 week old chicks for Mareks? I appreciate your help.