a well bred chihuhaua actually has a long and healthy life my grandfather had a 22 year old 2.5 lb chi female, i thought she was just gonna keep going and going, we used to joke that she was the energizer bunny in disguise. she was from one of his very first litters, and after her inital 6 months (hypoglycemia) she was extreemly healthy, never even had luxating patellas. a well bred chi should be a healthy dog as an adult. at aroudn20 though she did lose most of her teeth...(no teeth made the tounge stick out, she was tooo cute!)