The Blood of the Young!
Wired News ran a story today entitled Young Blood Makes Muscles Spry. It describes experiments where young rats have their blood streams hooked up to old rats and, after about 6 weeks the old mice received several health benefits.
Now it has to be a continuous transfer from a genetically identical being. You can't just drink the blood of the young like some medieval psychopathic aristocrat. (Though would that not be cool? Creepy, super strong old people stalking the streets with a thirst for blood. Night of the Dentures!) That being said, it makes you look twice at those baby carrier backpacks. It would only take a hidden I.V. tube and a kid who is an identical clone of the parent.
So in summary, if you see an older parent with a baby strapped to their back or chest who has a strong family resemblance, don't take any chances. Grab the person, scream hysterically and refuse to let go until the authorities arrive. You may feel silly, but you just may be stopping a mad scientist and his or her twisted plan to cheat death by parasitizing the young!
Then again this research may just be about discovering how to keep seniors healthy and cure degenerative diseases. Who can say. Are we really going to trust a bunch of scientists with their book-learning and creepy ideas?