Double offense

Kids and I were at Kroger.  We stopped to talk to my cousin and her little boy at the corner of bread and dairy.  After a few minutes, we parted ways, and I turned back to wave at her little toddler.  I guess it was one of those fold-your-hand-in-half-as-you-bend-down-to-his-level-and-smile-ridiculously kind of waves.   As we were walking away, Noah said, "No offense, Mom, but you looked kind of retarded when you waved."  I explained (again) that prefacing an offensive comment with "no offense" doesn't magically render it non-offensive.  Then I told him that "retarded" is not a good word to use, and he shouldn't even know it.  He said, "Sorry, but the kid is just little, not mentally challenged or whatever."