Characters and aesthetics

We know that Katherine and George have one daughter, but what if they had two?
Marlowe Jane Walter is 15, she is close with all of her siblings but closest with her older brother Cole. What will happen when Jackie arrives? Will the two become friends? or will the drama between the two brothers cause an awkward tension?
Based on the 2023 Netflix Adaptation of the original book by Ali Novak.
All rights to Ali Novak.