She's the Fastest

She's the Fastest is a and a former racing dog.

History
She's the Fastest was a racing dog at Springfield Downs, where her owner was the Rich Texan. She had a successful racing career until Simpson family dog Santa's Little Helper ran onto the track during a race, saw She's the Fastest, and took an instant liking to her. The two dogs mated on the track and lay contentedly together as the race continued around them. After the race, the Rich Texan gave She's the Fastest to the Simpsons because she wouldn't be any good as a racer anymore: "Once they fall in love, they lose their racing spirit."

After the fling on the track, She's the Fastest fell in love with Santa's Little Helper, became pregnant and had 25 puppies. She was never seen again after the puppies grew up, so it's possible that she and Santa's Little Helper broke up.

Homer was supposed to have had Santa's Little Helper neutered after the puppies were raised, but couldn't bring himself to do it, leaving Santa's Little Helper still able to sire puppies and subsequently impregnate Rosa Barks.

She's the Fastest wore number 8 in her last race, the same number that Santa's Little Helper wore in his last race before he came to live with the Simpsons.