I find the bantams and the silkies are more reliable than most of my larger hens.
One of our year old light sussex started sitting in the nest box = no clucking, but as she was sitting there I assumed she was broody. I put 8 eggs under her. She did sit well for 21 days, but not a peep out of her, no clucking, or squawking when I went near.
This morning I saw two little faces peeping out from under her. Discovered 5 chicks in all. Three eggs not hatched. Thought they may be a bit late. Maybe the hen knows better, as by this afternoon, she had moved to the other side of the pen and left the three eggs. I have put them under her again, just in case.