After you take your new puppy home, you may wonder what became of his litter mates, how they grew up, what kind of personalities they have and what they're like as adolescents and adults. Many pet owners enjoy the opportunity to reunite their dog with his siblings as a type of canine family reunion. As long as all dogs have been well socialized, this can be a fun experience for all involved.
Even if you get excited and look forward to the opportunity to pick your own brother or sister up at the airport after a long time between visits, dogs don't necessarily have the same type of emotions or memory for their siblings. Manage your expectations in advance of the reunion and don't be upset if the dogs sniff or play with one another, but don't display a frantic and excited range of emotions.
Just like any other situation where you bring together dogs who are basically unfamiliar with one another, it's best to make the introduction with each dog leashed and under your control. There's always a chance one of your dog’s siblings may not be well-trained or socialized. Another pup may be aggressive or attempt to reassert dominance remembered from the litter’s earliest days. A regulated reintroduction allows the dogs to get safely reacquainted with one another again.
While dogs don't remember people, places or things in the same way humans do, they instinctually are attracted to other dogs who share their bloodline, so there's a good chance your pup will have a positive interaction with his siblings. Anticipate a lot of sniffing, smelling and licking, and possibly some rough-and-tumble play, especially if the dogs are still young enough to remember being litter mates. Don't let physical contact get out of control, and separate pups if they become overly aggressive.
Even dogs who are related to one another can have an instinct to breed if they are unaltered and at the age of sexual maturity. If you are reintroducing siblings of opposite sexes, watch out for mounting behavior that could indicate mating. Dogs of the same gender may display this type of behavior in a dominant, rather than sexual fashion, which may be a throwback to their days as young puppies.