How Old Is Belly In 'The Summer I Turned Pretty'?

Reading 'The Summer I Turned Pretty', I was immediately drawn into Belly’s coming-of-age story. She starts the series at 15, right on the cusp of that magical yet awkward transition from childhood to young adulthood. The way Jenny Han writes her makes her age feel so real—full of hope, confusion, and those intense first loves. By the second book, she’s 16, and you can see her maturity growing alongside her relationships, especially with Conrad and Jeremiah. The third book jumps to her being 18, dealing with college decisions and the weight of more serious emotional choices. What’s brilliant is how Han uses Belly’s age to mirror her emotional journey—15 feels naive and dreamy, 16 is messy and passionate, and 18 is where she starts grasping adulthood’s complexities. The setting of Cousins Beach amplifies this, as summers become markers of time passing, each year a new chapter in her life.

What stands out is how Belly’s age isn’t just a number; it’s a lens for exploring themes like first heartbreaks, family dynamics, and self-discovery. At 15, she’s wide-eyed about love; at 16, she’s tangled in it; and by 18, she’s learning to navigate its consequences. The supporting characters, like her brother Steven and her mother Laurel, react to her differently at each stage, which adds depth to the storytelling. Han doesn’t shy away from the raw, sometimes cringey authenticity of being a teen, and that’s what makes Belly’s age such a pivotal part of the narrative.

I love how 'The Summer I Turned Pretty' tracks Belly’s age like a ticking clock. She’s 15 in the first book, all innocence and summer crushes, but by the finale, she’s 18—wiser, bruised by love, and staring down adulthood. Han uses those three years to show how fleeting youth is, especially when summers define your growth. At 16, she’s reckless with her heart; at 18, she’s picking up the pieces. It’s a masterclass in writing teenagehood.