Anja laughs like Beavis and Butthead. Now, my mother reads my blog and she is not going to know who that is. Let me see if I can find a sound clip.
Now, raise that up a couple of octaves and you have the Anja laugh. She's a tough sale though. She will smile at you willingly and often, but you have to do something really special to get the giggle. I used to get the giggle when I sang "Stars and Stripes" to her, with a few WEEEs thrown in. But now that's old. Now I get the giggle if I sit her on top of me and do tummy crunches. It's kind of like peek-a-boo, but a lot more painful. It's definitely worth it.
I'm sure that someday she will be like this. And she will laugh more than all four of them put together!!