We got our second dog when the first was about 16 months old. They're both male. We took Toby with us when we went to see Cameron at the breeder's to make sure they'd probably get along. Things have been mostly good between them. Cameron bonded to Toby right away. It's like having 2 brothers. They play, they fight, they tease each other... I think both dogs are happier in the long run for having doggy company.