Seems like everything I've come across just strengthens what I've thought all along: this was just a weird, unfortunate, heartbreaking conclusion that no one could have really prevented or predicted.
He had microphthalmos in his right eye from birth, and was blind it in because of optic nerve issues and the eye not being wired correctly to his brain and left eye. It makes me wonder if he was even born with the tumour and that was why he had problems with that eye, because the tumour mucked up the development even before his birth.
Thank you all for the condolences. It wasn't something I was expecting and I really only had a week to get used- or as used to as you can in that situation- to the fact that he was going to have to go so young, and I think the fact that he was dying because of something so… weird and unpredictable made it that much harder because I got a bit, irrationally, angry about such a beautiful, amazing little dog not even getting to see his first birthday. But in the same breath it makes it slightly easier, knowing this isn't an oversight that someone could have prevented from happening in the first place.
My vet showed me inside his mouth after he was gone; I didn't want to at first, but I'm so glad I did because it made me know I'd made the right decision at the right time. Even in just the week, the tumour had grown so much it was pretty much visible, pressing right down on the soft palate. The poor little baby must have been in so much pain, but right up until the morning before he went he was so full of life. He was totally blind, in pain, deteriorating before everyone's eyes, so tired, but he still wanted to play and chase the hose and do some tricks.
I feel so lucky to have got to spend five months with Fletch. He was just so special, and he made me fall even more in love with shelties, and I'll hopefully be bringing home another little fluff bum later this year if the litter I've got a tentative reservation on eventuates.
I made a little tribute video for him, and thought I'd share it here. You can't beat a sheltie: they've just got so much love, and so much life, and they're just gorgeous little dogs. I think Fletcher shows every single amazing characteristic of this beautiful breed, along with his own special flair that he brought to everyting he did. He was a really wonderful puppy, and I'm never going to forget him.
http://www.youtube.com/watch?v=Z89Yywkmheo