I'm a little worried about one of my kittens... Sasha's little grey tabby boy, named Jack by his new owners. He's big and healthy and gaining weight... he has already bypassed his sisters in terms of weight, even though he was one of the smaller ones at birth. But I am worried that he may be deaf. Their ears are all opened (well, not Missy's kittens yet) and whenever I approach the box and say "hi babies!", all of the other kittens raise their heads and look toward the sound, but not little Jack. I can snap my fingers or clap right next to his head and he doesn't flinch. I banged on the box quite forcefully but not enough to shake it and everyone jumped a little... except for Jack. So either he's just not at all phased by the noises, or he's deaf. What do you all think? It's not a big deal to me if he's deaf, but I don't know how his new owners will react, they may not want him. That doesn't concern me either, he'll stay here until he finds the perfect home. Are there any other ways of telling if he can hear or not?