Hen Roosting

We recently introduced three younger chickens to our flock of 7. Everything went really well, they still act like two little flocks but they are all in the same coop and everyone seems to be getting along and no bloodshed.

I have been going out every night after dark because the new younger chickens have been trying to roost in the nest boxes instead of on the roost, and I have just been moving them up, no big deal. But the last two nights the same hen, one of the older flock, has been just sitting on the cinder block that we have the waterer on, instead of up on the roost. Any ideas why she would do that? There would be plenty of room for everyone. I moved her up too, but I just wonder why one would start that?

 

Just HOPE it is something like that and not a health problem! I love all my chickens