I’m sorry for you're loss. Its not easy at all to let a broody hatch chicks in a coop/run with other chickens.
I learned a lot after reading a lot and semi-natural hatching 3 times.
One of my concerns was a sloping shelf up to the nest boxes. The small chicks knew how to get down. But not how to get up at first. I tried several things:
- made the slope very easy
- made a cardboard box on the ground
- put the small nestbox on the ground
the last is the best solution to adress this problem.
Want to know more?
First time I had trouble with a broody next to a nestbox with young chicks who started to peck hard on the head of curious chick. I learned from others keepers e.g to use a waterbowl with marbles to prevent drowning. And to give chick feed and water outside the nestbox area as soon as the mum goes out with the chicks.
A few weeks later I had real trouble with a rat coming in the run/coop through a hole. I lost 2 chicks.
Second time I had a little trouble with the space.
Last time was the best. I separated the 2 broodies who hatched together on one nest from the others. I could easily seperate a part of the run. I put a tiny coop/ big nestbox in it. At first on a bench. And after hatching I put this on the ground for a week until they learned how to climb the sloping shelf.
They grew up in this small coop with a run of 6m2. Which was great. The flock and the newborn could see each other through the hardware cloth. After 9 weeks I connected the two runs. There was some pecking but the chicks could get away easily and just learned their place in the pecking order.
Sorry I didn’t see your thread before. Oh and pictures alway help a lot if asking questions.