It is a good idea for children to have a pet. It does not matter if it is a cat, a dog, a rabbit, a salamader, a frog, a lizzard, a fish. Even a hermit crab. Any animal will teach the child so much. It will learn to help make them responsible. They can help by feeding the animal every day. Or by giving it fresh water. When a child is old enough it could scoop the litter boxes after you have properly taught them how. Or they could join you in taking the dog for a walk.
Children with pets at home will find joy in playing with the animals. If the dog or cat meets them by the door at night after school they may think that it is neat and special like the pet has been waiting for them all day. It is a great way for them to releive their stress and a playmate if they do not have anyone else to play with.