Chan

My nephew is 11 years old and his school is threatening to suspend him because they say his shots are not up to date, meanwhile his nurse says that his shots are up to date. The only shot he never received is the chicken pox shot that 7-8 years ago was optional (and from what I have found on the net it still is optional). Now his school threatened to suspend him and then the following day contacted my sister (his mother) and told her, my nephew didn't mention it to her because he thought he had done something wrong after his school told him that they were going to suspend him. So aside from there being no real grounds for the suspension they also made him feel like he did something wrong.

Bottom line, my question is can they legally suspend him over this and what can my sister do if they do suspend him? She refuses to get him the chicken pox shot (which doesn't really work anyways and IS optional) and she needs to know what she can do legally to prevent my nephew from being suspended.