I recall this feeling the desire to have dd4 read well early, partly because it would just be interesting, but partly because she was doing everything else so early, it just seemed inevitable. But so far she is just about normal in reading for a 4 year old. Lots of sight words, some attempts at sentence reading, etc. Her vocab is crazy big, uses words like mimic instead of copy, 'mock', 'literally', etc.
Convincing the preschool to have her in K was part of the reason too, but in the end other things convinced them that she should at least try, and either way her reading will progress as she sees fit.
Ds10 was pretty normal in his starting reading but after getting the ball rolling did shoot up several grade levels very quickly, so I wonder if dd will do that as well.