Integrating different aged chicks

[GiddyUpGo]

I know this question has been asked before in various ways, but I couldn't find anything specific to my situation, so I apologize if I'm asking a redundant question. I have 8 chicks that are a little less than 5 weeks old, and two chicks that are a little less than 4 weeks old. The two younger chicks were only a few days old when we got them and too small to be put into the rabble, so they've been in the house. We did put one of the older chicks in with them (the smallest) because they seemed to be very unhappy on their own. The older chick settled them down quite a bit and they've been content for a while.
Now they're getting a bit too large and messy to be kept inside and I'd like to integrate them with the older chicks. The problem is, the older chicks are psychos. We've handled them as much as we can but they still lose their tiny minds every time one of us walks into the barn. I'm afraid the younger chicks will get trampled. They're still considerably smaller than the older ones (the photo shows the size difference). But I'm also afraid if I wait too long there will be pecking and bullying. What do you think, is it safe to mix chicks at this age?

 

[rosemarythyme]

How much space/where are the older chicks housed in? If there's enough room I think it should be fine. It's to your advantage to put them together sooner rather than later, when pecking order starts to solidify more and it may be more difficult to integrate them.

 

[Sue Jess]

I have the same issue. My chicks hatched in the "bush" on the property, and were fine. I didn't even know there were any eggs. What a surprise. My hen hatched 12 chicks. After 2 weeks she was taken. Maybe a fox? I have 7 of the chicks and keep them in my backyard atm. When should I let them out into the bush with the rest of the flock? They are nearly 10 weeks old now.
There are 2 large coups on the property. 10 chickens live in one and 5 in the other. They swap around sometimes but not often. Please advise. Thanks.