neither one of my cats care about the guinea pigs, the mice we have, different story. Jack often climbs into the cage and pretends he is a pig for a while. They accually dont seem to mind the fact he is in there... continue with thier eating and such. during the day, the cage top is left off... I put it on at night.
I've read about studies done where very, very young kittens (before weaning) were introduced to rodents like mice as littermates. When they grew up, they had prey drive and all, but refused to hunt that type of rodent they saw as littermates when they were kittens.
I don't suppose you are going to adopt orphaned bottle babies though...?
I let the cats in the gpig room if someone's there to keep an eye on them and intervene if the cats get too playful, but otherwise the door is shut with the cats on the outside. (They have run of the rest of the apartment.) Even when the cats are just being playful, they could seriously injure a smaller, delicate animal like a cavy. I used to just smile when I saw the cats playing with each other, but when I imagine them doing that to one of my girls, I wince >.<
My cats don't touch the pigs. My one cat, Skittles, a fat calico, sometimes jumps into the cage and lays down. I think she likes the feel of the aspen. She hasn't done it lately though. In fact, I've only seen her do it once. My other cat is afraid of the pigs. He runs when he sees them coming. However, I've heard stories that cats have trapped, hurt, or killed guinea pigs. That's why you need to be careful. It really depends on the individual pigs and cat.
I would watch the kitten near the cage and see if she tries to go after the pigs. Watch when the pigs are out for floor time as well. Until you know more about her personality, and until she gets a little older and is out of the "playful" stages of a kitten, and is in the mature, lazy stages of a cat, you need to keep an eye out, and keep the cat blocked off from the cage. Either keep the pigs in a seperate room, or put a lid on the cage. They may turn out to be good little buddies, but you can't ever be too careful.
I'm not sure about kittens, but my 1 year old sphynx cat loves Spanky my skinny pig. When I have the lid off, she jumps in there and sleeps, she likes the shavings too. Once they were sharing a piece of hay. I watch carefully but they just sniff eachother, and then she goes to sleep and spanky goes about his buisness.But my cat is also declawed.