I have two speckled sussex pullets about 3 months old. Both girls are friendly and talkative. However, the one makes strange noises. I thought for a while she was getting picked on by one of the other hens. It is kind of a yelping noise. Today, I watched her. She makes the noise and shakes her head at the same time. I picked her up and stroked her - - - she was mellow and cooing. There are no signs of illness in her or the other birds. She is active and friendly and outgoing. Is this a normal form of communication for some birds? Is this how birds sneeze? Can birds have allergies? Has anybody ever seen a hea;thy bird shake their head and make a yelping noise ? ?