sky pencil holly dying
 

I planted three sky pencil hollies in the spring, and now one of them is
dying--or at least the leaves are brown and seem to be dying. The other
two are fine and they are all in the same location. Is this a disease
that might spread to the other two? It is possible that the one that is
dying had less water than the other. How tolerant are they of drought?
Thanks, Pat