Age gaps in chicks?

[Harmoni]

8-12 weeks is plenty old to be territorial.
It might work out just fine...but best to have a separate but adjacent enclosure for the new ones.


It's more like 100-300 feet, downwind,but if you can't do it, you can't do it....
.... and will have to assume the risk.

Biological/medical quarantine:
BYC Medical Quarantine Article

Yeah, our property is only 0.42 acres. And we aren't allowed chickens in the front yard which would be the only way.
I have a dog crate in the coop against the divider where the 8-12 weekers are and will set something up for outside tomorrow pending weather conditions. I'm picking them up this evening. I'm hoping they surprise me, but I will obviously be supervising interactions. Stinks to need 3 divisions lol. I read your article about introducing at 4 weeks. I think most of my big birds would be fine, except one. She was the lowest pecking order bird before I added 2 hens. That turned her into a bully to the new 2 and she's tried to attack the babies through the fence