To understand Josh, one must understand the tragedy of his relationship with the Covey sisters. For years, Josh dated Margot, the perfect older sister. He was folded into the Covey family dynamic so seamlessly that he became almost a surrogate son to Dr. Covey and a big brother to Kitty and Lara Jean.

He teaches Lara Jean—and the audience—that it is possible to transition a childhood crush into a lifelong friendship. He proves that being the "nice guy" doesn't mean you are entitled to the girl, but it does mean you earn respect and lasting love in a different form.

The resolution of Josh’s story is bittersweet. He accepts that Margot has moved on, and he accepts that Lara Jean’s heart belongs to someone else. But he isn't left alone in the cold. He retains his status as an honorary Covey. He remains the boy who will always help shovel the snow, who will always be there for Kitty, and who will always be a welcome guest at the house.

: The revelation that Josh and Lara Jean have a complicated history (and the kiss) is a major source of friction between the Song sisters. Character Legacy

Eventually, Lara Jean realizes that her love for Josh was, in many ways, a love for the idea of him. It was a love for the past and a love for the stability he represented. She realizes that they are better suited as family than as lovers.