single chick

it would be best if it had a buddy yes. Having it in the same room as the rest might help or it might stress it out if it can hear them but cant find them. Maybe if you can separate with a piece of Plexiglas so they can see each other and get close but the older ones cant hurt it. Putting a feather duster or a stuff toy in with it might help as well. Of course the best option is to buy him a buddy or two, as long as they are with in a week or so of each other and they are all strong and healthy they should be fine together keep an eye out just to be sure they get along.

 

I have had problems with chicks that were only a week apart, however I had some that were 3 weeks apart that did good, I did put then in the same coop but had them seperated by a fence for a couple of weeks.

 

Any chance you have a broody you can trick into thinking that she hatched this baby (aka: put an egg under her in the daytime and swap it out at night for the chick)? She'd keep her company and should keep her safe from the other birds. Just a thought.
I did it with my broody recently. She hatched just one chick and I took one that I hatched in the bator and put it under her. She took to it as if it were her own.
You could do the same thing if you get a second chick, put them both under the broody.

 

feather duster works wonders...

 

Maybe try a wanted ad on craigslist, the Seattle or Olympic Peninsula in either the farm and garden or wanted section. I've had great luck posting there. Or, if you want to drive a few hours out to Sequim, WA, I know someone who probably has some Good luck!

 

I had a single chick for two weeks until another clutch hatched. She was very lonesome in her brooder until I put a stuffed bird in there with her. Of course we spent a lot of time holding and petting her, and now she's our tamest hen. At two weeks I put her in with four newly hatched chicks at night and everyone got along fine in the morning. However, in my case the older chick was the lone one, and she was very happy to have company. I'd be worried that in your case the older chicks might attack the newbie baby.

Good luck! I hope it works out for you.