•  Why do you want a second pup? If you're thinking a second dog will take your place to entertain the first dog, forget it. You're the one they want. Dogs are pack animals, and a second dog will add play and joy to the day, but your attention and love is their goal.

•  Train your resident dog first before you think about the addition of a second dog and your resident dog can actually help with the training! Because dogs are pack animals by nature, it is natural for them to pick-up routines from their own kind.

•  Choose complementary breeds and personalities. Meaning, don't match a tiny toy puppy with a big, rambunctious dog. The toy dog could easily be injured, even if no injury was intended. Matching an older dog experiencing the aches and pains of age with a hard-playing youngster is also a poor plan. Your resident dog does not get to choose his new lifemate, so be thoughtful on his behalf.

•  In general, choosing the other gender is your safest bet. Have a male? Pick a female and vice versa. Select a younger dog, as dogs close in age are more likely to have disagreements. Bringing in a dog older than your resident dog can create tension.

•  Realize the costs. Double everything.

•  Consider the joy. Double it, too, then add a bit more.

Adopting Two Littermates

Taking two puppies from the same litter sounds great - in theory. But a good theory doesn't always mean an idea is good in practice.

Here are some of the common problems that can occur when raising siblings:

•  Puppies bond to each other and not so strongly with you. This can be countered by lots of individual time with each dog alone, but this is time intensive for the first few months. Skip this important step and you might have dogs that have problems when separated.

•  One bored puppy can be naughty; two can be downright inspired! This is one situation where 1 + 1 = a LOT more mischief.

•  Housetraining two pups is more than twice as difficult as they will be more active, leading to more need for bathroom breaks. And note that getting two pups in and out smoothly can be a challenge.

•  Command training is harder with two as one dog needs to be put away while the other is learning, and the confined dog may bark throughout.

•  Most serious is that, as the pups mature, aggression can develop. Does it develop every time? No, but when it does, it can be hard to manage and serious.

Consider getting one dog, then adding another when the first is over a year old. By then, the first dog should be well trained and solidly bonded to you, which will make life easier when you bring in the new addition.