It is more than enough, Clarissa. It sounds as though he is a very bright little boy and that you have been a very attentive parent. You have obviously given him a lot of stimulation and training. The most unusual skill you mention is the subtraction; children generally learn to add before learning to subtract (maybe that’s just part of the human condition). And I think it is marvelous that he knows some sign language.
It sounds as though your son has not resisted your attempts to teach him these skills generally not found in children until they are a couple of years older than he is. That reassures me you are not pushing him too much. But do watch it. You are going to have to walk a tight rope between providing enough stimulation for him and not being so concerned with accelerating his learning that he begins to resist and to “tune you out.” Try to find special areas of interest and let him develop those. But be prepared for teachers a few years down the road who are going to assert that you have pushed him too much.
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