More broody hens

[That old chestnut]

I've got a selection of hens (light sussex, buff orpington, silver laced wyandotte, araucana, a couple of gold lines and a few crosses from these) running with a couple of peckin bantam cockerals. For the last 2 years I have hatched a number of batches out in the incubator with some success. I also have a separate coop with 3 Belgian D'Anver hens and a male. I wasn't going to hatch anything this year as we have more eggs than we use and end up giving them away.
Anyway, to get to the point, one of the D'anvers is broody and has been sitting on 5 eggs for a few weeks. She seems fine and has been getting off herself to eat and poo. I was tempted to just leave her with the others as I didn't really intend to raise any more and am not too bothered if they hatch successfully. I wasn't sure how the others would react to the chicks and gave in yesterday and moved her into a spare rabbit hutch (it does have an integral run). She settled onto her eggs straight away.
One of my hybrids has also been broody for 3 days and when I lifted her she was sitting on 10 eggs, quite clearly a seletion from most of the other hens. I have also moved her into an old coop, but she took more than 1/2 hour to settled and sit back on her eggs. Will this be ok? It was quite warm yesterday, but how long can the hens stay off before it affects the eggs?
Would the fact the eggs are a mix and range in size (big orpington eggs and much smaller bantam cross eggs) be a problem? They were laid within a few days of each other.
Also, how and when do I introduce the hens and their chicks back with the rest of their flocks? Would it ever be ok to have left them with their eggs in with the others or would the chicks be harmed? I have a coop with a huge run, but the big flock tend to free range all day (we have a very large garden), but the D'anvers stay in their coop and run as the male is extremely aggressive towards everyone and everything.

 

[Clodagh]

Mine free range with their chicks once the chicks are old enough, but they need different food which is a pain. Also the hen needs to be fairly high in the pecking order to keep herself and her chicks safe.

 

[millsandboon]

1/2 hour off the eggs is fine too.

 

[Alexart]

I had one I accidentally shut out of her box for 4hrs on a cold day and the eggs still hatched fine so 1/2 and hr isn't going to hurt them and is quite normal. You can mix big and small eggs together, if the eggs were all started off at the same time even if laid over a few days then they should all hatch at the same time, but if she started brooding them and others came in and laid eggs in the meantime she may get off when the first ones hatch and leave the others even if they are near hatching so keep an eye on her.
I always seperate broodies off from the main flock as some hens can be bullies especially if the broody is a low ranked bird, they can also get killed sobetter to keep them apart until they are fully feathered and almost too big to fit under mum, the d'anvers I'd keep away from the bigger birds for a bit longer just to get them a bit bigger as they are pretty diddy!!

 

[That old chestnut]

Thanks for your replies. The D'anvers are in a separate coop anyway, but the male is quite aggressive so I will wait until I can sex them before I reintroduce them.
Both hens are sitting really well and I am having to lift them off a couple of times a day for food and water (and a poo!). I'm quite excited and can't wait to see the chicks running around with their mums. As I said I've only used the incubator up into now.