Of course its ok! My grandfather is 7 years younger than my grandmother!yea yes it is the first answer is just total nonsence stupidness because all girls and boys have some kind of curiosity about each other genders about at the age they hit puberty and even if u still dont hit it its normal to "like" someone of the other gender now likeing someone of the same gender is something else and not normal but nonetheless O.K.
It's when the girl starts introducing the boy to older aged wrong practices that it is inappropriate.