old enough?

I have an 8 month old cat that is seperated from other other cats (a year in a half)... and its a hassle. I had them seperated so she couldn't eat their food... but would it be okay to put them together now?
Also, this is about dogs, but I couldn't find anything about it on the internet. My husbands dog had to be put to sleep because of gastric dilation the other night. They said he was licking his lips excessively the night before. I read that when they lick their lips it means they are nauscious. My dog is constantly licking his. Is this a sign that something is wrong with him???

I'll put this in Behavior for the question about your cats. Hopefully someone will be able to answer about your dog question there too.

Thanks!

I wonder if there is a really good forum like this about dogs? If anyone knows of one please let me know. I am sure Peppersmommy would appreciate it too.