Found a little kitty head.

Last week sometime, our fat little Evie had her kittens in a box with a blanket set up for her under a shelving area. We counted 7 kittens at the time then left her alone to do her job. Today she was out of the box and we decided to check on the kittens. We found the same 7 meowing away with closed eyes but then over in the corner of the box I seen a fuzzy little ball. I picked it up and quickly realized it was a head. There is no blood on it or any signs of a body ever being eaten in or killed in the box. Did she eat her baby and then thoroughly clean up the evidence better than any government hit man clean up crew? Is this normal during kitten births?

Sorry about the kitten.   Normally a mother kitty will only eat a kitten if it is sick or hurt with no chance of survival.  And No, this is not normal.   Keep a close eye on the mother's behavior and the kittens, for she may try to eat the others because of a sickness the kitten has picked up.  Young kittens are very voluble to disease because of their weak immune system.  

Okay thank you.

Follow up question. Is it normal for her to spend so much time away from her kittens? She is hardly ever in her box with them and when she is is only for a couple minutes, not enough to feed them it seems. She's not outright hostile towards them but she doesn't seem to care unless one of the two small dogs gets curious and ventures near the box, then she tears him up.

Be prepared with KMR formula mix and bottles for back up feeding, that is a big litter! Very strange to find only the kitten head. Maybe the kitten wasn't fully developed? 

As said, mothers will sometimes eat any dead kittens to keep predators away. Fortunately it does not happen often. Can you move her to a room where she cannot leave the kittens too far away? Usually the sound of them mewing will call her back, but if she goes too far she cannot hear them. I agree that you should get set up with KMR, bottles and needle-less syringes in case you have to take over. Are you weighing the kittens every day to be sure they are gaining weight?