We had one Yorkie for 15 1/2 years, & I always said next time we get a puppy, we are going to get two. It always bothered me that Mocha seemed bored or was CONSTANTLY looking for me, & I always felt anxious when we had to be gone. My 24 year-old daughter (who doesn't live at home anymore but for some reason we see her more than when she did live at home
) bought a chihuahua in December. We bought Kodah in March & she absolutely loved Paisley, but it took about two weeks for Paisley to feel the same. I actually looked forward to Paisley coming over because Kodah just loved her. Five weeks later we got Stormy. Paisley & Kodah would have nothing to do with her for the first few days, but gradually they accepted her. Now they are all three great together & we call them the "rat pack" - the three of them together weigh less than 10 lbs. Paisley, the chihuahua is now 8 months, Kodah our Yorkie is 5 months, and Stormy our yorktese is 4 months. All three have such different personalities & we absolutely love watching them wrestle, play & nap together! I agree with the others, you will never know until you try - but for me, I do not think I will ever have just one!