My 11 year old bull dog is in his last days. I've personally never had to take a pet to be put to sleep. The thing is, I don't believe he's currently suffering, but taking care of him is becoming a big chore. When he was 7, the glaucoma in his eyes got so bad, I had to have one of his eyes removed. Shortly after that, he lost his vision in his other eye. So for the last 4 years I've had a blind dog. That alone is alot of work. Recently I believe he developed dimentia as he will get lost outside and just walks in circles. He also has developed myositis recently which is muscle inflammation in his head and looks like part of his head is collapsing. This usually leads to pain and won't allow dogs to open their mouth to eat etc. However, he doesn't seem to be in any pain. He still eats like normal. Anyways, I don't when there's a right time and I've never had to do it before.