Hows THAT for a depressing idea?
It isn't depressing at all!
We all have to make way for new blood and new ideas. It is good for the race as a whole.
In a sense, our own children are our guarantee of immorality so long as humanity survives. We pass our genes, and our memes, on to them.
We are all threads in the tapestry. Stand back from your own thread, and behold the beauty of the whole.
Burn-who doesn't want to live in this world forever.