And, although this value is subjective, I also think it depends on what one reaps from interacting with that organism, compared to what one gives to that organism. I am a financial and occasional social burden to my parents, but they would say I am worth it, because I bring happiness into their lives that outweighs the majority of those sacrifices.
I feel extremely sorry for those parents who will have to take care of severely disabled or retarded children for the rest of their lives, period, and will most likely never get to see those children grow or improve in any notable ways. That must be quite difficult indeed.
"Gentlemen, the verdict is guilty, on all ten counts of first-degree stupidity. The penalty phase will now begin."--Divine, "Pink Flamingos."
"The strong rule the weak, and the cunning rule over all." HS!