Kittens-cat flu?

Hello all,
I have another question about my kitties and the momma cat.
The momma was a strayed that i took in in may,she got pregnant a few weeks later...right before her spaying appointement.Anyway i decided to keep the kitties and do it after.
She always had a bit of eye-goo and dark crusts around her nose,it seems to come and go.I took her to the vet and he didnt say anything about it.
Now the kittens have it too,especially the lighter one.
They sneeze once in a while but not that much and they all seem very healthy.Very energetic and big!
I was wondering if that could be cat flu and if it is do they need medications?
The kittens are 6 weeks old now,i have 3 of them.
One died very suddenly at 3 weeks i took em all to the vet right after and she said they seemed to all be doing fine ( momma cat included).
Thanks
I included a pic of the lighter one,if you look you can see the dark crust he has around his nostril.
http://i89.photobucket.com/albums/k2...y288/dmigu.jpg
http://i89.photobucket.com/albums/k2...288/dmigu2.jpg

Well it doesn't really look that bad, their eyes I mean. You could take a warm washcloth and wipe all their eyes off, get that goop off. If it doesn't let up or the sneezing continues or gets worse or especially is you see green goop coming out of their noses when they sneeze and get them back in. I would think the vet can give you some amoxi or eye ointment or something.

At 6 weeks, they could go in for their first shots. I recommend taking them in this week, just to be sure.