When I was little, my brother and I were both allowed to get pets (he a dog, I a cat)...we got them within days/weeks of each other. Because they were so little, the basically "grew up" together and were great pals. When my cat died, I got another cat and the dog thought this one would be his pal as well...well, no, she didn't think so. Anyway, she tolerated him, then we brought in another puppy who loved everybody/thing, but became a little scared of the cat because she didn't put up with his craziness. First dog died, so second one tried to cozy up to the cat more, which she tolerated but didn't care for. Cat died and I got another one. This one was used to dogs and thinks my dog now is his bestest buddy (though the dog is still a little skittish because of the previous cat)...but they're still buddies, playing and snuggling.