? 2 weeks apart.. always in seperate cages?

They should have no trouble being put together. I had week old chicks that I put day olds in with, then a few days later, put more day olds in with. It would probably be better to try and put them together as soon as possible. The older they get, they seem to get more set in their ways. Just watch them for a while when you first put them in there, to make sure they are getting along. Might wait a few days till the new ones have recovered from their trip. That way they won't seem weak, and be good targets. Just make sure they have plenty of room to move around. Mine are a mix of standards and bantams also, and they get along fine.

 

I put my day olds in with 1 week olds this summer and they were just fine. It helped that the day olds were standard sized breeds and the week olds were bantams - so they ended up about the same size Now that whole group is almost 9/10 weeks and they run with the group of 16 week old millies and 1 EE. In fact the 9 week old Lakenvelder pullet sleeps on the top roost with all the other top birds now.

 

I've put chicks of different ages together many times and have never had a problem. I do give them plenty of room, however, which may help.