Just to clarify what I said: with my son (two grade skips), the differences didn't become a big deal until 8th grade. At that point, the kids in his class were mostly a lot more developed than him and interested in things (like girls) in a way that hadn't hit him yet in the way it had hit them. The boys' voices had all changed and his hadn't. That kind of stuff.I'm really thinking about primarily physiological reasons for a lack of connection at times (though there are others, depending on the kid).