Maybe he's just being a teenager. That's it's own catagory in my experience. lol
Maybe he's not interested in watching all the attention D will most likely get from all the long distance rellies. Could be a bit of jealousy there. He hasn't really been the focus for a bit of a while now has he? That's not a criticism classic. It's just the way it is sometimes when you have a high needs child around.
I'm sure you'll deal with it when you've cooled down enough not to act like a teenager yourself.