So we're thinking in a couple years about buying another dog. Someone that sadie can play with and chase after,and romp around with...rather than our 8 pound cat. Sadie is pretty high energy,being both lab and pitbull,but she's not bouncing off the walls. So i'm thinking of a breed that will wear down with her but has enough energy to keep her occupied and doesn't wear down before her. She's only 6 months old and she wore out my girlfriends parent's german shepherd husky mix. Any suggestions on a breed? I'm thinking of maybe a medium sized breed,but i'm not closed off to another larger breed,but nothing over 60 pounds.