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, dogs, and horses, but have fewer interactions, and are not counted as household members.

The Sims
In The Sims, only one small pet was available, the fish in the Poseidon's Adventure Aquarium. Sims 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 the selected Sim's Charisma.

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. The Sims 3: Pets feature various kinds of minor pets, which can be caught outdoors like other collectibles. Minor pets can be kept temporarily in the inventory, but they might eventually run away if kept for too long. Minor pets need to be placed in terrarium. Animals in aquariums and terrariums must be fed regularly.

Here's the list of minor pets in Pets:
 * Pet rocks
 * Birds: Blue Gold Macaw, Catalina Macaw, Cockatoo, Congo African Gray, Crow, Falcon, Spotted Sixam, Yellow Naped Amazon, Cardinal, Easter Bluebird, Gold finch, Lilac Breasted Roller, Nuthatch, Parakeet, Pigeon, Owl
 * Lizards: Anole Lizard, Ancient Dragon, Gecko, Chameleon, Pygmy Komodo Dragon, Agama Lizard, Texas Spiny Lizard, Iguana
 * Rodents: Chinchilla, Hedgehog, Squirrel, Rat, Shrew, Womrat, Chipmunk
 * Snakes: Yellow Python, Garter Snake, Emerald Tree Boa Snake, Malayan Krait Snake, Yellow Chondro Python, Scarlet King Snake, San Francisco Garter Snake, Iridescent Shieldtail Snake, Mini Python
 * Turtles: Barbour's Map Turtle, Spotted Turtle, Eastern Box Turtle, Indian Roofed Turtle, Red Eared Slider Turtle, Pygmy Tortoise, Spiny Turtle, Western Painted Turtle
 * Ant farm

In The Sims 3: Supernatural, there are some storage cabinets suitable to showcase up to 8 insects and butterflies. Additionally, Sims can store insects and butterflies from the their inventory inside the cabinets.