I had a similar situation happen. Had 4, lost 3, then got 9 babies, kept them in the brooder until they were feathered up, then put them in the coop. The one remaining adult chicken that I still had, was the most shy & docile of the 4, when there were 4. At first when they were all together, she was kind of a bully and would peck on the top of little ones heads, however, they weren't brand new babies and they had some growth on them, but still a lot smaller and they would squawk and run away from her and they had plenty of room. Then I isolated her and then brought her back in and she still did it, but not as much, now after several weeks, she only does it a very minimal amount and I can tell that as the new ones get bigger, she will probably give up the top rank, because she was always very passive and already showing signs that she's not the alpha type. At this point it seems that she really likes the company and happy with the others and not alone anymore.
So to answer your question, yes it can be done. But as others have said, just be careful and it depends on lots of variables, type of bird you have, type and age that your adding, personality of the hen that you have left, size of the coop/run, amount of feeders and waterers available, things inside your coop/run to distract them, etc.