Oh my goodness! Have I got a story for you!
We bought two hamsters at petco, they were together in an aquarium when we got them and they swore they were both girls. WRONG!
They were quite prolific. They had SO many babies and then they got cannibalistic! It was disgusting! My son came screaming to me one day unable to put into words what was happening.
I went to look and there were baby hamster pieces everywhere and only 3 hamsters left out of many.
So we isolated momma and poppa, who had blood all over their faces and hands.
There was a larger baby in with the other two, he continued the blood lust!
So we were left with momma, poppa, and baby cujo hamster.
My son was crying and said he did not want them any more because "Their mean and scare me!"
So we released them in the back yard for the neighbors cat to draw out karmic retribution.
Now before all you animal lovers start leading me to a hanging tree I will defend my actions this way. It is no different then feeding them to a boa constrictor, which is common practice.
In my opinion hamsters are nasty creatures If you are going to get one only get one! (they were teddy bear hamsters)