My son the dinosaur

The little man is now two and is growing more independent and sure of himself by the day. He loves all things "dinosaur", as mentioned in a previous post, and likes to walk around stomping and roaring whenever he can. For his birthday his Aunty bought him a tail which also roars. It's great, but he wasn't too sure about it at first, but the other day I managed to snap him having a play with it.

I've noticed too that he has started to play act a lot more and I began to wonder at what age that usually starts. He's starting to pretend he's a dog, coming up to me barking and scratching behind his ear (very cute), as well as interacting with two toys making them talk to one another and feeding them, and so on. It's so interesting to watch him do these things, some of them seemingly coming out of thin air. So, my question is, how old were your kids when they started to play act?