RE: Is it possible for a fawn to have a rack...
+1 for fawns with antlers. You get an early-dropped fawn with no stress and eating right - and his buttons will push through the hide, and he'll grow a small pedicle with small spikes.
Whether or not those "antlers" arise to your definition of "antlers" is debatable...
But they'll polish and shed them just like any other buck.