I've just looked at CNN and there's a piece from an hour ago there's no confirmation. I'm not sure why the baby beheading became a big deal - we are sure they killed and burned babies, children, women and even dogs. At point blank. We are pretty sure they raped (there are quite a few evidence by now). We know for sure they beheaded adults (I saw pictures of beheaded soldiers).

Oh they also make it a point to murder hostages and send their loved ones a video of the murder. Great bunch of people.

If they did or didn't behead a baby doesn't really matter much imo. If they didn't does that somehow make everything alright? They did plenty.