Tuck Everlasting: Natalie Babbitt

This is an old classic that I had read as a child and wanted to refresh my memory. Winnie is a bored only child one summer and adventure finds her in an unexpected way. She is led by curiosity into the family woods where she finds a boy drinking out of a stream. When she tries to join him he tells her the water isn't good for her. His parents (the Tucks) come and wisk her away, then tell her a story about basically the fountain of youth. They had drunk the water and hadn't aged in 80+ years. Coincidently a man looking for the fountain of youth overhears the story and plans on selling the water to whoever will pay. The Tucks, knowing the misery of never aging and never being able to stay in one place too long, end up killing him. They quickly leave town. The boy leaves instructions for Winnie to wait until she is 17 (his age) and drink some of the water. He promises to come find her. She ends up putting the water on a frog she befriended. The Tucks come back 40 years later and are saddened to find her gravestone. We are lead to believe she got married and lead a normal life, but there is a lot to think about. The author leaves out 40+ years of story that we get to piece together how we want. My first question was why didn't the boy come back? The ending was bittersweet in that the Tucks were glad Winnie didn't drink the water because never-ending life is not a blessing, but they really cared for the girl and hoped she would be part of the family.