Introducting a new bantam to my big girls

[k8]

I'm having a problem. I adopted a little cochin (with a little prompting from my friend's daughter). She's cute as can be -- I think she's a young pullet. I've got 5 big girls in the chicken yard that don't like her. Of course, there's this pecking order thing -- they peck her right out of the yard (being a banty, I suppose they can do that). But we have big hawks and dogs and cats that could get her. I actually thought she was a goner last weekend when she went missing for 24 hours. When I did finally find her sitting just as pretty as she could be in the coop, I decided to bring her in the house until she was bigger. But I'm afraid that the longer she stays in the house, the more spoiled she will get so that when she's big enough to go back out to the coop, she really won't be accepted. Despite having safe places for the little cochin both in the yard and in the coop to hide, I worry.

Is there a trick to getting my chickens to get along? Shall I just let them fight it out?