Thewebguy, I will answer this for you. Concerning your first question, whether it be a cat, dog, bird, fish, etc., there are maintenance fees to upkeep the pet besides, of course, the actual purchase of the pet. When making a budget to how much you want to spend monthly on pet care, just make sure to include food, grooming, and toys and miscellaneous. Usually anywhere from $50 to $100 dollars a month depending on what type of pet you have. Dogs and cats are more expensive due to higher needs, and pets such as fish and birds are less expensive, less needs.
With children, as with adults, having pets around has a soothing and relaxing factor, and brings companionship to the persons that have the pet. Also, it just teaches children how to take care of things and act around something that is not human. Which is always great experience to someone growing up.
I suggest you go to a National Park close to where your located. Most National Parks have enough animals in them for your child to see that are safe. Otherwise, just visit you local zoo to get a great glimpse for your child to see animals.
Thewebguy, great questions, and I am glad to answer them for you.