Adding a chick at 4.5 weeks?

[aank4]

Hi all -
We found out one of our four pullets is likely a cockerel, and I was able to find another pullet of exactly the same age and breed to add to our group (our roo will need to be relocated soon, since we're in town). I will likely quarantine for a little while before adding her to our little group (how long do you all recommend?) - but otherwise, do you think there will be squabbles? Or are they still "chick" enough to go with the flow? I don't want to just drop her in to the brooder box if she's going to be pecked and harassed.
Thanks!

 

[Opa]

I think I would keep her away from the others for at least two weeks. Then when you place her in with the others watch closely. I've found that I've had to put on in for a little while then remove it for several days until they became accustomed to each other.