Yes, once of my quail sat stubbornly on eggs and hatched a little clutch in October! Unfortunately at day 3 something happened overnight panicking them all and she seemed to abandon them and some had managed to get through the weld mesh.
I came down in the morning to find 6 tiny frozen corpses and was so upset I just went back to bed , blaming myself for not bringing them into the house but she had seemed like such a solid Mum.
I went out them put them away and one of them gave the tiniest gasp. I have never seen more dead looking creature and it's breathing rate was about 4 a minute.
Rushed into the house with it in my hands, breathing on it to try and warm it up. Yell for the OH to get me a hot water bottle so I could rest it on that while I got a box, made up some honey water and general resuscitation kit etc.
OH thought I was making a bit of a fuss and should just put it under the grill while I got sorted!!! He still insists it was a reasonable suggestion!
Anyway despite looking mostly dead he picked up with heat and honey water and mum even took him back. They lived in the spare room till he was 4 weeks and fully feathered and almost fully grown. He is now the head (well only) boy in my group and although a little smaller than I would expect is a happy and, ahem, active boy.
I feel awful for the little ones I lost and although brooding outside is possible in terms of mum keeping them warm I have learnt my lesson in terms of the unpredictable nature of the rest of the world and how small a gap they can get through.
Have learnt my lesson and will always brood them in controlled circumstances in the future.