harrasment by nurse manager

Hello all. Recently I have been floated quite regular to a dementia floor. I work with another float and regular staff one of whom is brand new. She's been there just as long as I have (3mos). Anyways, she has been the target of harrasment by the nurse manager for that floor. From the moment she started working there the nurse manager was overheard saying mean things about her like she looks goofy and she walks funny. The nurse manager follows her around and double checks her work and checks her pts frequently. She also tells the LPN's on the floor to watch her and report anything this aide does. Up until recently there was no incident just the unprofessional behaviour by the nurse manager but yesterday the aide was called down to the nurse office to be "witten up" for not changing a resident by the time highlighted on the CNAAR sheet, there is a two hour window. This aide has always been given the hardest assignments and we all help her out however we can. Instead of the 10 am change the resident was changed at 10 30. The nurse manager went around and did her regular thing by following this aide and promptly decided that this warranted a write up. Now granted this resident was not really wet and she is alert enough to say she needed changing. This whole thing has made the cna very uncomfortable to the point of quittting. I cant say I blame her. My question is what should this aide do? What would you do in a situation like this if you were witnessing this or was the aide yourself?