Tell him everyone has their quirks. Don't deny he has them, or everything you say from then on has no value (I say this from the standpoint of having been there, as a child on the spectrum). To this day, anything my mother says to me is little more than words. Her thoughts were, if she lied to me and I believed the lies, that made everything okay.
Honesty is critical with children on the spectrum.
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They tell me I think too much. I tell them they don't think enough.
