Pekes’ main problems are eye issues and breathing problems, resulting from its tiny skull and flattened face, and skin allergies (and hotspots). An especially common problem is eye ulcers, which may develop spontaneously. Pekes should never be kept outside as their flattened faces and noses can develop breathing problems, which makes it difficult for them to regulate their body temperature in overly hot or cold weather. Their long backs, relative to their legs, make them vulnerable to back injuries. Care should be taken, when picking them up, to give Pekes adequate back support: one hand under the chest, the other under the abdomen. Short legs give some Pekes difficulty with stairs; older dogs may not be able to go up or down stairs alone.

These dogs can be stubborn and jealous. This is not a dog for someone who wants a dog that always comes when it is called. Pekes are sometimes aggressive, especially to other dogs. It may take a long time for Pekes to get used to any other dogs except puppies, mates, and siblings. However, Pekes can be properly socialized with dogs and other types of pets and can become fast friends. It is easy to believe that Pekes know that they are royalty and expect you to know it, too. This might make them unsuitable for the first-time dog owner. The Pekingese personality has been compared to a cat, although this isn’t quite right. Where a cat can be trained, a Pekingese needs to be convinced that the training is beneficial to him as well as to you. But, if they love you they will do anything for you, even fight to the death to protect you.

The Pekingese is generally a one-person dog. They decide who they like best, and it might surprise you. They more than tolerate the others in their person’s life, but that person might have to withhold some attention from the Peke if there is a danger that the Peke sees a child as a rival. Most healthy and well-trained Pekes are fine with children. Unfortunately, because they are among the ‘cute-and-I- know-it’ breeds, many people don’t properly train their dogs and end up with difficult jealousy problems

source : wikipedia