Pullet that does not lift tail

I went to pick up a trio of SLW's a while back and there was a small Silver Penciled Pullet in the pen too. She was smaller(younger) then the rest of the birds. She looked very meek, my thoughts were she was being picked on. The man had no use for her and sent her with the trio. So this girl has adjusted to her new home, is not being picked on but seems to be a bit of a bully herself. She is not sick but she has never lifted her tail? Not when she walks or runs? It is somewhat comical to watch her waddle around looking like a pigeon! Should I be concerned or is it possible there is an underlying problem?