Hi Tam,I have had two hamsters for pets on two separate occasions. I spent a lot of time with each of them on a daily basis, and kept their cages really clean (which is quite a laborious task). While they were healthy, they both died at just over a year old. It was heartbreaking both times. This is especially difficult for a young child. Hamsters generally are very fragile, labor intensive, and die young.
Someone else mentioned guinnea pigs. They make wonderful pets, and live up to 7 years. They also require cage cleaning (and it will smell if you don't keep up with it), but any animal takes work. They are cute as a button, make neat noises and are very cuddly and loving if treated right. Just make sure not to put a male and female together, they W I L L procreate, and procreate, and procreate. (I learned that the hard way.)