I dont get the whole kids thing talking to a spirit that no one can see...
Didn't we all have imaginary friends when we were kids and spoke to ourselves and all that!
And what do you think that imaginary friend was. Kids see things because their minds haven't been conditioned by society yet to be closed minded. Kinda like society puts blinders on some of our "perceptions" or "senses". We condition ourselfs to see only what is in this realm that we touch, feel, see, taste. I think the best way to describe it as, like a TV set, we only get the channels that cone in strongest, the others are static---but sometimes on a good day, you may get the Spanish channel.
I had a cousin that when little would say, "Grandma says hi!", now this is in a crowded room, and whne asked where is she, "she's is over there...", pointing to a chair she used to sit in. Now, this lady died when the girl was a infant, she wouldn't know what she looked like except for photos, but the child was three yrs old when she blab these things out all of a sudden. This is called Second Sight.
Now, she can't see anything like the sort.