It's one reason I am so impressed that you can do what you do is that you have to deal with your kids dying. I turn into a blithering idiot every time I read about a kid dying before his or her time. Seriously. I know it happens. I know I can't stop it. I know there are other people it hurt a lot more than it hurts me. But even so.....
So it's ok for you to be sad. For as long as it takes, whatever that is.