8-year old son bitten by gopher. Er did not treat because gophers "very rarely" get rabies. Once symptomatic, death is certain. Vaccinate anyway?

Rabies vaccination. Consider (1) the history of any cases of rabies from gophers in your locality; it sounds like the er mds are saying it is very rare; and (2) consider the circumstances of the bite. Did the gopher go after your son for no apparent reason, or was your son trying to play with it. If the latter, then this is a "provoked" bite which also carries less risk. If so, i think it safe not to vaccinate.