I went to visit my Daughter today and was told visitation was canceled. Is this fair to their parents?

It's not fair, but prison is not there for fairness, it is there for the housing of inmates until their sentence is served under rules that we on the outside can't imagine.  Visitation is considered a privilege, not a right - and when they take it away it is usually for some sort of egregious act from a group of inmates. The rules that are imposed are not to punish the visitors, they are there to keep the order and control the acts of the inmates. Visitation may get cancelled for a variety of reasons - there might be some security issue, a group punishment stemming from punitive actions of a few or other reasons to use loss of visitation for inmates behaving badly. Prison is not fun or fair.