Sometimes the lessons we have to learn in life are not fun.
I had to have our cat, Rainbow, put to sleep last night. She had lost an alarming amount of weight recently and was having many other issues. After x-rays, it appears that she had cancer in and around her liver which was causing her much pain and discomfort. I know that putting her to sleep was the right thing to do for her, but it's still hard for me and to see the upset it causes the children.
This is a lesson in life (or death) that I wish we didn't have to learn.