The length of a dog’s tail is an inherited trait. The allele for short tails is dominant (T) over the allele for long tails (t). A dog breeder mates two short-tailed dogs (parents). One parent is homozygous and the other is heterozygous for this trait. A litter of twelve puppies, all with short tails, is produced (first generation). The breeder mates one of the first generation dogs with a short-tailed dog from another litter. A litter of ten puppies is produced (second generation). The breeder is surprised when one of the second generation puppies has a long tail. Describe the genetic make-up of the parents and puppies that produced this inheritance pattern.