The answer is complex. Duchess' mate was a purebred (presumably Turkish Angora, like Duchess) stud. Duchess, however, wasn't content with a snobby tom like him, so she had a fling with a moggy stray. As a result, her daughter has a separate father from her sons.
All My Kittens can be read here.
All My Kittens provides examples of:
- Animal Gender-Bender: Bob is described as "black, with white paws and occasional patches of ginger and tabby". Most calicos are female. Toms with such colourings are also usually sterile, though it's technically not impossible for one to be fertile.
- Child of Forbidden Love: As Duchess notes, she was not supposed to breed with a common stray. The vet offers to euthanize the toms for being moggys, but Madame Bonfamille refuses.They were common cats. Bob's kittens, the product of her naughty, childish fling in the woods. She had betrayed Madame, who had been so kind and spent so much money to provide a good father. How could common cats live in such a noble household? Madame's pedigree, she knew (for humans have them too) was longer and more ancient than her own. This was why she had selected an aristocratic cat to be her companion. She could not be expected to provide for these mongrel kittens.
Yet the white kitten was the product of a joyless, mechanical pairing, while her sons had been conceived in love. And whatever their paternity, she loved them all equally. She had done wrong, but these little innocents, the result of that wrong, must not suffer for it. There could only be one solution: she must leave Madame.
- Disappeared Dad:
- Cyrano is Marie's father. He was a stud cat.
- Berlioz and Toulouse's father Bob is a traveling stray. He was probably attracted by the scent of Duchess' heat.
- Full-Name Basis: Duchess refers to Bob as "Robert".
- Furry Reminder:
- Cat mating isn't particularly pleasant for the female. Duchess doesn't enjoy it.
- Kittens from the same litter can have more than one father.
- Duchess' pregnancy only lasts 9 weeks.
- Hotter and Sexier: It's not for titillation, but the fanfic does center around the topic of mating in extensive detail.
- Idle Rich: Cyrano is a lazy, pampered pedigree cat.
- Married Animals: Duchess' owner refers to chosing a mate as "choosing a husband", even though there's no legal marriage involved.
- Mature Animal Story: The oneshot answers the question of the parentage of Duchess' kittens. It deals with topics concerning animal mating and sex.
- No Fathers Allowed: Like in real life, father cats aren't usually in their kitten's lives. Duchess had children with two different toms that she'll most likely never see again.
- One Night Stand Pregnancy: Duchess' sons are the children of a moggy stray. He had wanted her to run off with him, but she wouldn't leave her owner. This explains why her sons look so different from her and her daughter. Duchess almost runs away because she fears her owner will kill her sons for being mixes, but her owner loves all her cats regardless of their parentage
- Only Known by Their Nickname: It's noted that Duchess doesn't know her pedigree name.
- Prefers Proper Names: Duchess refers to the Street Smart stray Bob as "Robert", even though he only mentions his name as "Bob".
- Preppy Name: Duchess' first mate has the snooty full-name of "Cyrano de Bergerac".
- Predator-Prey Friendship: It's mentioned that Duchess won't eat mice and that she's even friends with one (Roquefort).
- Title Drop: To the original film:"Among humans, the most noble men and women in society are known as aristocrats. Bon - you four will be aristocats! Will you do that, my darlings?"