It used to be that Cooper would make faces, or change his facial expression, pretty much randomly, or in response to some stimulus, like me smiling at him or being startled by something. But he has discovered he can make faces ON PURPOSE and that they will illicit a response from those around him. An example is the face he is making in the picture above. He has just begun making these funny faces. He seems to really like it. He will raise his eyebrows and squint his eyes, or get very serious and shake his head as if to say "that would be a VERY bad idea". It is vastly entertaining to me. At this point he will reliably say about three words. I don't think it would matter to me he if never learned to talk more if he and I could sit and make faces at each other all day long. There are cultures where that is the only form of communication, body language, or other forms of non verbal communication. I think it is GREAT fun.
Of course that would make being a functional member of American society just a bit challenging, so I expect we will continue to encourage verbal communication. But for now we having a good time, making faces at each other and giggling along the way.