First of all I would I would have some tests run on her to see if this cold is a cold or maybe it could be a disease. I have several cats here that have a runny nose, runny eyes, coughing at times, etc. And I have had them checked repeatedly for everything including Rhino and FELV. Everything comes back negitive. They wanted to take one of our cats in for science to figure it out but we dont have the heart to let our kitties become science experiments. Not all of them have it. Out of 16 cats 4 seem to be immune. Out of the 4, 3 were brought into the environment and 2 are the mothers of the others. Its not a genetic thing either because one of the 4 that dont have it was a stray we adopted and she was pregnant when we brought her here. Now the kittens have it but she doesnt.
Anyhow, you never know what it could be, or left untreated what it could become. Get your babes in for a look over.