How big is the fawn. Lot of people, myself included, call a spotted fawn as a fawn and then after they have the solid brown hair (maybe 2 1/2 months old) from then on till they are about grown they are called yearlings. If the fawn is big enough to fend for itself there is no reason not to take the doe, and if it is a young buck then he will probably stay in the area the rest of its life as a doe will runtheir young buck offspring out of the area. Mother nature's way of helping the genetics.