Dog
Dogs were introduced in The Sims: Unleashed. In Sims 1, a family can adopt a dog by going to the Pet Center in Old Town, or a Sim can befriend and adopt a stray. However, the Create-A-Sim section of Sims 1 does not allow you to create pets.
Dogs must be housebroken by praising them when they relieve themselves outside and/or scolding them when they do it inside. A dog may - or may not - try to drive El Bandito the raccoon off a lot, but will ignore the burglar.
In The Sims 2, dogs may be created in the Create-A-Pet section of Create-A-Sim. Sims can adopt dogs or puppies using the phone or by buying them on community lots that sell pets. Players can also get a pet dog in Apartment Life by buying the pet cage in the pets section of buy mode.
The Sims: Breeding Dogs
If a family has a male and female dog, they may breed. The puppy will appear as a small tent with a dog-face above it. You need to keep the mother's motives up for the three Sim days it takes the pup to become an adult, otherwise she may neglect it, in which case Animal Control will come to take it away. When the puppy becomes an adult, you will be asked if you want to keep it as a pet. If you choose not to, the new dog will disappear from the game, but the family will get some cash.
The Sims 2: Breeding Dogs
If there is both a male and female dog on a Sim's lot (both dogs do not need to be owned by the selected Sim), and there is a pet house available, a Sim has the option to command a dog to try to have puppies with another dog. The Sim must have a good relationship with the selected dog to successfully command it, and the dog must have a good relationship with the other dog to successfully breed. Pregnant female dogs show little noticeable signs of pregnancy, and can go to work as normal. They give birth after three days like human Sims. In The Sims 2, puppies are much more self-sufficient than in The Sims and can feed themselves (provided there is food available) and sleep on pet beds without the help of a Sim or their mother. Puppies can also learn Behaviors. However, puppies (as well as kittens) cannot go up stairs without the help of a Sim, and they cannot get jobs or learn Commands.