I have a cat and two rats. I wouldn't say they get along! If your rats are quite big, I expect the kitten will probably be quite wary of them to begin with, but once it's grown, who knows? Cats are still semi-wild and will most likely hunt small animals and birds. Having said that, I have known cats who cuddled chinchillas and rabbits.
 
When my cat was a kitten, we had a hamster also. The cat was DYING to get hold of it until one day he put his paw through the cage and the hamster bit and (as hamsters do) held on tight! It really scared the cat, and now, 14 years later, he still doesn't like animals in cages.
 
I would say that if you do get a kitten, just be very careful. When I got my rats I was very clear that if the cat killed them, it would be my fault for letting him get close enough. It takes careful co-ordination to make sure they don't cross paths!
 
If you do get a kitten, please be sure to keep the rats' cage off the floor where the cat can see them. That was the mistake I made and now my rats aren't scared of the cat, which was a stupid thing for me to do.
 
All the best

 Yeah definitely wouldn't get a kitten cause when it gets bigger it will probably eat your rats....

 I heard if a cat/or other pet grows up with a rat they'll might learn to love each other!