We got them as 6 week old pups. We were told they were Boston Terriers, but as they grew, we could see clearly that there was another breed there. We called their momma's owner, and he told us that the neighbor's Jack Russell was the daddy. Our vet confirmed it! Those two are 2 peas in a pod! Very energetic & loving, and love to play with their "siblings" (my human kids)! They adore belly rubs, and have even brought us a couple of birds they killed as presents! Love my furry girls!