Sheba the Border Collie / Shetland Sheepdog mix puppy at 5 months old—"Sheba is a Border Sheltie. Her mom is a purebred Border Collie and her father is a purebred mini Shetland Sheepdog."
The Border Sheepdog is not a purebred dog. It is a cross between the Border Collie and the Shetland Sheepdog, also called a Sheltie. The best way to determine the temperament of a mixed breed is to look up all breeds in the cross and know you can get any combination of any of the characteristics found in either breed. Not all of these designer hybrid dogs being bred are 50% purebred to 50% purebred. It is very common for breeders to breed multi-generation crosses.