Fish  

Fish are also affordable kid friendly pets.  They are easy to maintain and are available in a variety of species.   

The only caveat is that a tank with a proper filtration system is required, which can be rather expesnive. Certain breeds of fish can be as well.  And not all types of fish get along with one another in the tank, so make sure you do you research and ask for advice in the pet store. 

Fish are not only beautiful to look at, but for adults they act as a de-stressor and provide a soothing atmosphere as well. 

They are certainly not as hands on as owning a dog or cat, but they can be a rewarding pet for the whole family.