Integrating chicks into young flock

[PomPom21]

Hello. I have 1 week and a half old chicks and 11 week old chicks. When and how do I integrate them.

 

[aart]

Are the older chicks living in a coop?
Are the younger chicks in a brooder?
Dimensions and pics of coop and run set up might help here.

Here's 3 good setups to integrate chicks young:
https://www.backyardchickens.com/articles/integrating-new-birds-at-4-weeks-old.72603/


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