Your cats have URI ( upper respiratory infection/s). The "goopy" stuff on the cats eye, is infection. If not taken care of, cat CAN LOSE EYE! Call the Vet and explane what is going on, he/she will get you a perscription for an opthamic gel. If your ok with it, try to take a warm wash rag, or wet kleenx and wipe the eys off to remove any discharge, then put the gel in the eyes. Do this 2-3 a day and within a few days to a week. Your cat should be good as new!
Like i said, It can be serious. As with any infection, if not treated it can spread! I have seen a simple eye infection spread very raipidly! And i work with MANY cats that only have one eye because somebody didnt want to take the time (and small amount of money) to help them!
This is going to sound funny...but I bet it's Chlamidia (sp?). My kittens had this problem and when we took them to the vet, they were diagnosed with Chlamidia...the mother cat passed it on to them while she was pregnant. You have to get it treated...it's fairly easy to treat, but if untreated they can go blind, or worse. I'd DEFINITELY call the vet!!!
I'd take her to the vet. It could be a lot of different things and they can probably tell by looking at it.....but if it is infection - it won't clear up on it's own and could possibly lead to vision loss in the eye.