Long story short, I had to re-home Kavanaugh (the aggressive rooster). Now Patty is broody. I only have 5 hens, and would like to bring in a few more chick's but I've read many, many times that you need ot quarantine them and incorporate them slowly for disease issues. I've also read that people have snuck the chick's in under the hen at night to make an instant family.
This is not a HAVE to situation and I want to do what's best for my hens. Educated opinions please!!!
I think I can help you with this. I think what you are referring to is a current broody adopting a chick that she did "not" hatch. I have done this with success with a batch of chicks that I ordered from a hatchery. When I received my order I planned to give my broody the chicks but when I received my order I found that I had one chick that was failing to thrive. I gave her to my broody, she adopted it raised it and today the chick is health and full of life.
I will link the post from my blog below. This is the story of Miss Katie my broody and the chick that she adopted and raised for me. I hope this helps or at least answer some of your questions.
https://thekuntryklucker.blog/2017/05/24/sometimes-you-just-need-a-momma/