I went out to the old bantam's coop a few minute ago and notice my two year old serama hen standing next to the waterer and not moving. i picked her up and she feels a little underweight and her shanks were freezing cold, which is strange because it's very warm here today. her comb is a little pale and she's not responding when i move her beak back and forth. i brought her in and offered water but she's not drinking it, even when i dip her beak in. she mostly keeps her eyes closed. she does not have any nasal discharge, no sneezing or coughing. i havn't had the chance to examine her manure yet but in the coop i havn't seen anything out of place. all the other chickens look perfectly healthy. this is my little sister's favorite bird so i don't think she'd let me just cull her so please don't suggest it unless you think that is the only option. any idea on what's wrong?