No Scorpio, don't fight with Wiley. She's a senior member and has lots of valuable info to share. You might need her help later. She just mistook you for one of those dopes that posts about junk like paper-doll websites in a cat forum just to "chat" like they think they are on AOL. I think you meant to ask how to prevent it from happening again since you have already cured your kitty. I found this on a Google search. "Transmission or Cause: Ear mites are passed from one animal to another through close contact. Mites also can be transmitted through the environment to an animal." Do your kitties go outside? I have never dealt with mites even when I had outdoor cats in the past. But your kitties have big ears so they must just be more open to infection. But mites can cause all kinds of problems and even deafness so keep an eye out for any re-infection of spreading to the other kitty. I usually try a Google search for just about anything. Use key words like "cat ear mite cause" and you get a ton of information.