First, welcome to PT! This is a great forum to learn about all pets!

I am sorry that your furbabies are having troubles. I have no experience with this particular symptom, but I am sure that some of the longtimers and the fosters will have some suggestions and advice.

I guess my first thing would be to head to the vet since it seems like it is contagious since all of them are having the same symptoms. Keep us posted.... and pictures are always enjoyed!