Who dat ?

I feel like my emotions have run the full gamut of late, from delight and joy at the things Zack says and does, to pure desperation when he is 'contrarian' and will not do anything you ask him to. This coupled with the announcement that we are expecting our second child in September, means that I really am not the most rational being in E14 (our postal code) right now.
I was very grateful when chatting to an acquaintance 2 weeks ago, that her son was also a head-banger, and now a biter. She was very sympathetic about it and also very relaxed, which gave me hope for the future. I know it's 'just a phase', but that's no comfort when you're right in it, so talking to someone who's been through it makes me feel a little better.
Zack's latest thing is to say "who dat?" when he hears a noise outside / in another room. It is just too cute. He'll often suggest some answers too, but they're pretty repetitive, "Daddy?" or "Kelly?" or "Nana?". Another thing that happens all the time is him saying "Amy's house" and now "Harriett's house", when we're in the car - like he's telling me where we're going. The truth is that Amy lives in Australia - which I've explained numerous times (with map), and we visit Harriett on Thursdays. It's amazing actually that he already associates directions in the car with a destination.
Another association that he's got sorted out, is that waiters or waitresses bring apple juice. So when we're in a restaurant with friends, Zack will catch the eye of the passing server and say "Apple juice" in an expectant kind of way. At this point, I'll get the enquiring look from aforementioned staff member. Then Keith and I will laugh. Remarkable little people.