Can't I just say "grow up" instead of "grow up on" here?
Native speaker’s answer
Rebecca
Usually the phrase "grow up" is more common than "grow up on", but in this case, the preposition "on" is used to describe the location of where she grew up. So in the context of the phrase "grow up" here, the preposition "on" is necessary since she uses the noun "beach" right after the phrase, and the preposition "on" usually goes with the noun "beach", "farm", etc. Ex: She grew up on a farm. Ex: I grew up in a big city.