Two are better than one! Cats like humans need companionship! When adopting a kitten it is good to get two. They keep each other occupied, it helps social development, and it is twice the cuteness! You can see cats bond as they groom each other, sleep side by side, and rumble and tumble around playing! So keep in mind next time you adopt or if you think your current cat needs a friend: two (or more) cats is ideal!
Some shelters will even give you a discount when you adopt several cats or kittens at one time! Also remember kittens are tiny and cute but they grow. Adults 1 year or older have such low chances of being adopted. So here is an idea if you want two kittens, get one adult and a kitten instead. The two can play together just as much as two kittens could and that kitty cat bond will be strong!