My co-worker is having a difficult time learning her job. There are some aspects she is great at.t?

The employees in her dept talk about her negatively in front of everyone. The are constantly attaching her and speak to her disrepectfully. They are also condescending. I want to help, but I don't know how. We are at different levels. She is more of my supervisor. We started at the same time, so we have developed some form of kinship. We are union. What would be a good way to help her keep her job and get all of the other nurses off of her back. The Director of Nursing is also on the band wagon to get rid of her. So, we can't go to her supervisor and ask for istance.