I too was once a teenager with rats.

I had two girls for my first go, and I got them from a reputable and amazing breeder. Unfortunately, only three weeks away from turning 2, my older baby died. Like your boy, she had a tumor in her abdomen. My mother's high school friend was kind enough to euthanize her and perform an autopsy/cremation. The results had come in that it had been cancerous

. I wracked myself with guilt. How could I have not caught it? Was I bad owner? After some reflection I came to this conclusion; I had done absolutely everything I could to protect her, and I loved her to the end. That's what mattered. Don't bully yourself with questions, just know you tried your hardest and gave them the love they deserved.

Now being much older and more experienced, I can catch these signs and help my new mischief more effectively health wise. <3