grieving for hamster

Question
Last weekend our Syrian hammy Sam(10mots old) passed away. I noticed that his left eye was protruding enormously and we took him to the vet, thinking he had fallen or contracted some eye infection. Turned out he had suffered a trauma to his eye(theoretically climbing up his cage, falling and injuring his eye).
The vet suggested having the eye removed but would be terribly risky and Sam may not have survived the anaesthetic. He was suffering so bad;sqeaking at us and in terrible pain. I didn't want him to suffer anymore and gave the vet permission to euthanase him, which she suggested to be the most humane option.
My Son(11yrs) who Sam primarily belonged to is heartbroken. After we buried Sam and disinfected/stored away Sam's things, He can't go into his bedroom anymore (as that's where Sam stayed) and he isn't coping well without him. I've tried (and still am) to support him thru this and validate his grief but am not sure what to do next. Any suggestions from yourself  and/or others are very welcome as we're finding it hard. I too feel very guilty as I'm the one who effectively ended his life even though my son understands why I did what I did.
I hope you can respond to our letter and thankyou. Joanne.

Answer
This would be a good time for you to explain to your son about life and death. This was Sam's time. While you don't know exactly how he injured himself, on an animal his size removing an eye isn't always the best option. From the pain he was in it was unlikely he would get over the trauma on his own and most owners would have chosen euthanasia. Sam is no longer in pain and would be happy you gave him peace. I would not feel guilt. If your son understands, then he knows that keeping the hamster alive would have resulted in Sam being terribly unhappy, and what would he have done in that situation? Letting him go would be a very adult thing for him to do. When your son is ready you can get another hamster if he so chooses.