Here's a thread on this subject. It raises some points not yet discussed.
Raise with flock? thread
https://www.backyardchickens.com/forum/viewtopic.php?id=215937&p=1
How long a hen will mother chicks varies quite a bit. Other than the hen's personality and the strength of her broody instinct, I don't know what controls. Most broodies will take care of her chicks until they can take care of themselves but occasionally you will get one that does not..
Raise with flock? thread
https://www.backyardchickens.com/forum/viewtopic.php?id=215937&p=1
How long a hen will mother chicks varies quite a bit. Other than the hen's personality and the strength of her broody instinct, I don't know what controls. Most broodies will take care of her chicks until they can take care of themselves but occasionally you will get one that does not..