So said ds2 yesterday at tea time. He may not have been being profound, he's a bit obsessed about going to pizza hut at the moment (never been) but has been told he can't go when we have ds1 with us obviously. And last week he was going on about ds1 not being autisitc when we drove past pizza hut, I suspect it may be linked.
However he did tell me he thinks ds1 will talk "when he's a grown up". So there we go.