They are only 1 week old! How stupid could I be? It's almost like they vanished into thin air, not a single clue as to where they went, but I think I know the guilty party. In the mornings, I let the chickens out when I go out to feed the horses before going to work. The cat and the kitten follow me to the barn. This is usually about 6:30am, so it is still quite dark. I suspect our 12wk old kitten slipped under the run gate and got the little ones. The kitten is black so this would be quite easy for her to do, I just didn't think she would have the nerve to go in there and I certainly did not think she would fit under the gate. I have since fixed the gap so, hopefully I won't be missing any more chicks when I get home this afternoon.