It also took him quite a while to learn how to give a kiss. Something about the fine motor control of his facial muscles was a little slow to develop too...I got a lot of slobbery kisses while we were working on that particular skill. He's able to give absolutely "normal" hugs and kisses now, but believe me, I don't take a single one of those for granted! I'm also impossibly grateful for how loving a child he is...even though we are still working on his social skills, whatever issues we have stem from him being too affectionate, not the opposite.
Just now, I was sitting in the kitchen drinking my coffee and reading the news on my iPad. He came up to me out of the blue, gently took my face between his hands, and kissed my forehead. That is something I've done to him (and his siblings) literally thousands of times--it is one of my go-to expressions of love with my kids. I've never seen him do it before, though. He just used my own gesture on me and I am undone.