Staffordshire Bullterrier
AKA the Nanny dog
The Stafford is considered a family pet and companion dog, and is among the breeds recommended by the KC for families. Relative to the breed's ancestral progenitors, the AKC states: "From his brawling past, the muscular but agile Staffordshire Bull Terrier retains the traits of courage and tenacity. Happily, good breeding transformed this former gladiator into a mild, playful companion with a special feel for kids."