I'll try to be brief: If you are going to buy your toddler (age 0-4) his first pet, may I suggest a cat or dog? And, may I also suggest that you take responsibility for this helpless animal, since your toddler will most likely not be ready for this kind of commitment?
Why it's dangerous for your child:
Hamsters are WILD. If they are mis-handled, awakened several times during their natural sleep cycles, dropped, or anything of the sort, they WILL BITE. Hamster bites can lead to infection. And depending on how serious the bite is, it could become anything from a first-aid issue-- to a trip to the emergency room--or in rare cases, even disease.
Why it's dangerous for the hamster:
Hamsters need a quiet, stable living environment. They also need food and water daily. The excitement a toddler will feel, and act upon, especially the first few days, will cause much stress for the hamster-- who's first few days are the most crucial in it's new home! This can very easily lead to mishandling, waking it up several times daily, food/water shortage (toddler forgets to feed hamster, toddler plays with water bottle and forgets to put it back in the cage...)
Dwarf hamsters are not as easily tamed as syrians, and also escape more easily---making a poor first pet for a child. Syrians, who are more easily tamed, would be better for this task, right? WRONG. Syrians are VERY nocturnal. Is your child going to stay up all hours of the night to play with the syrian? Or is it that the poor syrian will get woke up several times daily (against it's natural cycle) to fulfill your child's desire to be entertained? Too much stress will lead to Wet Tail. To put it boldly, your child can end up stressing the hamster to death, literally.
Also, when the hamster gets fed up with being mis-handled by your toddler and defends itself the only way it knows how, chances are high that your toddler will "punish" it in exchange for the bite--- or that YOU will abuse the hamster for biting "your baby."
Let me say it as nicely as I can: A hamster is NOT a good pet for a toddler. Because of it's wild nature, a hamster should ONLY be acquired after a responsible adult, or older child, who truly loves and cares for animals, has done their research and knows they are up for the challenge of hand training/further needs. Anything short of this is setting a helpless animal up for a miserable life of abuse and neglect. Please think before you buy a hamster for anyone- especially a child!
