Small pet

Small pets are pets that live in aquariums or cages and can be taken out briefly for Sims to play with. They require less attention than cats and dogs.

The Sims
In The Sims only one small pet was available, the fish in the Poseidon's Adventure Aquarium. Sims obviously have to feed the fish and clean the tank to ensure they remain healthy.

In Livin' Large, the guinea pig was introduced. If the cage wasn't cleaned for a long time, and it bit a Sim, the Sim would become sick. The fastest and easiest way of curing this sickness is to buy the guinea pig painting and look at it.

Many more small pets were introduced with The Sims: Unleashed. Sims were able to go to Old Town and purchase a variety of small pets, including iguanas, turtles and small birds such as budgies and love birds. All of them require feeding and cleaning occasionally, but they don't need as much attention as cats and dogs. However, unlike cats and dogs, they can - and will - eventually die, no matter how carefully they are cared for. Parrots and Cockatoos can also be bought in Buy Mode, for §939 and §749, respectively. Sims can not only feed them crackers, but also talk to them, which boosts their Charisma. (The Sim's, not the bird's!)

The Sims 2
In The Sims 2 base game, the Aquabox Five-Gallon Aquarium is available.

With The Sims 2: Pets Sims could buy a bird or womrat. Their cages can be bought in the pet section of buy mode and then "stocked" with the animal, at which point the player may select its breed/appearance and give it a name.

Womrats resemble guinea pigs (in fact, they seem to just be guinea pigs that go by a different name), and have exercise wheels, which real-life guinea pigs cannot. There are a variety of birds available, including what appear to be parrots, macaws and parakeets. Both birds and womrats must be fed daily (about twice a day in the case of womrats) at a small cost, and their cages must be cleaned every couple of days. Cleaning a pet's cage builds Cleaning skill, but not by much, as it only takes a moment to finish. Birds can be taught to talk and then talked to; both activities build a Sim's Charisma while also providing Fun. Playing with a womrat or bird is also a source of Fun. However, birds and womrats do not have to be played with or interacted with in any way; all they really require is food.

Both birds and womrats will die if they aren't fed. If their hunger levels get low, food-related thought bubbles will appear above their heads, warning the player that they need food as soon as possible.

If a bird cage is left open too long, the bird will fly around the house. It may cause a nuisance by getting in Sims' way while flying around, and it cannot be fed, talked to or played with while doing this, but it will not cause any other problems and will eventually return to its cage.

Birds and womrats are the only pets that young adults can keep on college lots. They can be placed, cage and all, in a Sim's inventory at any time; when removed from the inventory, they will be just as they were before. In this way, a Sim who moves to another lot can bring his or her pet along.

If The Sims 2: Seasons is installed, Sims can catch butterflies and then put them somewhere in a jar as a decoration. Butterflies can't be fed or played with and if they remain in the jar for too long, they'll die. To avoid this, a Sim can release them outside.

The Sims 2: Apartment Life allows Sims to buy a small pet version of a dog that never leaves its pen. Child and older Sims can feed, play with, and watch the dog, and can clean its cage, but the dog will never be outside of the pen unless it is being carried. The Pets expansion pack is not required for this..

The Sims 3
In The Sims 3 many aquatic animals, including fish, frogs, snails, and crocodiles, and insects can be caught and placed in an aquarium or terrarium.

Animals in aquariums must be fed regularly but can essentially live forever.