A man/woman (whichever is opposite your gender), is immortal, because (s)he and his/her family have drank from a fountain of youth, not knowing what it was. You are now in love with this person and have felt this way long enough that you know (s)he to be your destiny. However, the only way you can stay together forever is if you drink from the fountain of youth and become immortal, too. If you do this, however, your family and everyone else you know will grow old and eventually die, and you will never be reunited in heaven with them, or your loved ones that you have known, who have already died. On the other hand, if you don’t drink from the fountain, you will grow old and eventually die, and the person with whom you are in love will never see you again, and be condemned to an eternity of loneliness and only memories of you. What would you do?
(From Tuck Everlasting, by Natalie Babbitt)