The Shetland Sheepdog, often known as the Sheltie, has been intentionally bred small. Shelties are ideally suited for the terrain of the Shetland Islands in Scotland. While they resemble a rough Collie in miniature, they are not a true miniature Collie, as there are many differences in appearance. Shelties are intelligent, family oriented dogs that can be as happy in an apartment in a city as in a house in the country.
The Shetland Sheepdog is an outstanding companion dog and is intensely loyal. It is lively, intelligent, trainable, and willing to please and obey. Shelties are loving, loyal, and affectionate with their family, but are naturally aloof with strangers; for this reason Shelties must be socialized. Some can be quite reserved. Although they are excellent family pets, Shelties do especially well with children if they are raised with them from an early age; however, their small size makes it easy for a child to accidentally injure them, so supervision is necessary.(Wikipedia)