Tuck Everlasting by Natalie Babbitt (1975)

“But the thing is, you knowing about the water already, and living right next to it so's you could go there any time, well, listen, how'd it be if you was to wait till you're seventeen, same age as me- heck, that's only six years off- and then you could go and drink some, and then you could go away with me! We could get married, even!"

Tuck Everlasting, Natalie Babbitt, 1975, p. 71-72