John Ambrose McClaren is a childhood friend and possible love interest of Lara Jean Covey.
Although he is mentioned throughout the entirety To All the Boys I've Loved Before and even makes a short appearance in the first book, he just becomes a recurring character in P.S. I Still Love You after receiving Lara Jean's letter to him.
Before the events of To All the Boys I've Loved Before, John had been in Lara Jean's most romantic moments, which happened on a rainy day.
While Lara Jean's and Peter's relationship is being strained by Genevieve, Lara Jean and John start exchanging letters. Those letters bring them closer again, making Lara Jean wonder what would've happened if she had gone out with John instead of Peter.
Eventually, Lara Jean remembers the time capsule they buried in Carolyn Pearce's garden and decides to invite all of her middle school friends to open it. Being on bad terms with Peter and meeting John again, she starts seeing John as a potential love interest, especially after spending more time with him due to Stormy being his grandmother.
It is revealed in P.S. I Still Love You that John originally sorted out some flowers in Lara Jean's backyard to ask her out to the 8th grade formal until Lara Jean's father found him in the backyard, laying out some flowers. Lara Jean's father thought John was doing some backyard work around the neighbourhood and gave him some money to pay for the job. Because of that, John left Lara Jean's house and he never actually got to ask her to the formal.
Towards the end of Always and Forever, Lara Jean it is shown that he now has a girlfriend called Dipti, who we learn meets John after she beats him for gavel in Model UN. It is also mentioned that he will go to William and Mary after being rejected by UNC.
John Ambrose McClaren is known to look like a young Robert Redford. He is blonde, has rosy cheeks, and is, according to many, very handsome.
In the second installment of the movie series, P.S. I Still Love You (film), he is re-casted as African-American and he has brown hair and eyes, and from the looks of it, even more handsome.
In the second book, we learn a lot more about John Ambrose McClaren and his relationship with Lara Jean. When he was young, he was described to have had a stutter, which made him shy; he was said by Lara Jean to be "kind of in his own head", and not very confident in himself or in his social life. However, when Lara Jean meets him again, she is surprised at how much he’s changed: he is more confident in himself and more sure. John Ambrose is, as described by Lara Jean, "sweet", and an "easy person to be quiet with". He likes reading; he doesn’t mind being alone, but is well-liked by many and has lots of friends. He is also known as smart and very good in Model UN.
According to Lara Jean, he is less vain than Peter, but also self-conscious, and embarrasses easily, especially when dancing. He is also described as someone rather pensive, nervous, and more easily flustered than Peter, who takes everything in his stride and isn’t easily fazed by anything.
He and Lara Jean were friends in middle school until he moved. He had a huge crush on Lara Jean and planned on asking her to formal in 8th grade.
Peter and John were childhood friends. When they were little, they earned the nicknames "Butch Cassidy" and "Sundance Kid", Peter being Butch and John Sundance Kid.
Stormy is John's great grandmother, but since Stormy believes calling her that would reveal her age, John calls her Stormy. John is Stormy's favorite grandson and she greatly adores him. John visits Stormy several times at the nursing home, mainly because Stormy wants to set up him up with Lara Jean.
John and Genevieve were childhood friends.
Chris and John have known each other since childhood. During the game of Assassins, John has Chris's name, so he follows her to a gas station to tag her out.
Trevor was a childhood friend of John.
Allie and John were childhood friends.