How to introduce new chickens to a one chicken flock?

I posted this question one other time on a different section of the board. I apologize if this is a repeat for some folks. Just wasn't sure what the appropriate section was for this question. Thank you in advance for the help.

I was given a ~4 week old pullet that is now about 8 weeks. It currently lives with us in the house but it is about time for it to go outside in the coop we built for it. It cries when left alone and I'm worried that it will be lonely by itself outside in the coop. I realize that chickens are social animals. I want to help by getting 2-3 more chickens so it can have some friends and start its own flock.

The question is, what is the best way to do this? Should I buy some chicks from the local hatchery and when their old enough try and introduce them slowly using some of the techniques suggested in many threads on this board. Or is it possible to wait until she is old enough and slip a couple of fertilized eggs in her nest?

This is my first time raising chickens and hadn't planned on raising one or any but now that it's happening I want to do it right. I'm clueless and open to any and all ideas.

Thanks!

 

Thank you for the advice. Quick question, after night fall, should I just put the new friends in the run and let them go up into the hen house on their own or should I put them directly into the hen house, or should I place them directly on to the roost?

Thanks!