I have 5 horses, 2 dogs and a house cat. Most are not what you'd call young. Some day there is going to be a lot of weeping when illness, injury, old age, or euthanasia come knocking, an unwelcome guest, over and over again until the slate is washed clean for the next generation. In earlier years I have watched my horses, dogs and cats go to the beyond. Nothing about any of this mortality thing is very nice. One of my best friends just had her precious feline friend put to sleep. My brother has a dear elderly and infirm dog of nearly 17 years of age. Death comes when expected and when it is not. That they are merely animals, or that their short lives give us "practice" for the real losses, human losses, does not hold water with me. People are made with an instinct to become attached to things. We may get over having to hold that teddy bear, but as we age there are new things to get attached to. Members of the opposite sex (or not, depending on the person I guess). Our careers. Our children. Our home. And, our animals. Along with human attachments, I think the bond we have to our animals is unusually strong. Witness the folks flooded out of their homes in New Orleans after Hurricane Katrina. They wouldn't leave without Fido. And those who were forced to, they often entered a depression, not for their bricks and mortar and boards and furniture. No, they mourned the loss of those eyes looking back into theirs. A case can even be made that spouses, children, and friends can be replaced (and often are), but not another soul can replicate that animal friend that you nurtured, trained, loved. He or she that depended upon you every day - utterly. In their final hour, you know that there must be a heaven or no life is worth living.