First of all, name a more iconic father-daughter duo than Hopper and Eleven on Stranger Things 2. You can't! These two had us crying all season long, and a eagle-eyed Redditor just noticed a heartbreaking/warming detail about their relationship: Eleven is now wearing the blue band that Hopper used to wear around his wrist.
As you can see in the below photos care of Reddit, this blue band clearly belong to Hopper's daughter Sara. We can see it in her hair during a flashback scene, and it appears several times on Hopper's wrist throughout the first and second seasons. Obviously, it means a lot to him, and he never takes it off.
However, in the final moments of Stranger Things 2, we can see that Eleven has a nearly identical band on her wrist—implying that Hopper (who, as a reminder, adopted Eleven) gave it to her as a gift. Here's a closer look:
*tears up, starts sobbing, turns on Netflix, isn't seen or heard from in 12 hours.*