I have fond memories of playing LEGO with my brother and our friend from daycare. My brother was like a mini engineer; he's always had a knack for building things, so that was his area. I'm awful at building things, and never had much interest in it.
Instead, I loved to create new characters and invent elaborate back stories for all of them. I knew each character's name, what Hogwarts House they were in (my LEGO world was/is based off of Harry Potter), who their family members were, what their personality was like, etc.
I'd like to say that my brother's building talents and my writer's imagination blended together in perfect harmony, but I don't know whether I really told him much about my characters. I remember using a couple of his buildings for Hogwarts, but I guess I mostly kept to myself.
I'm still creating new characters and adding more depth to their personalities and past. I've got a file on Google Drive dedicated to just LEGO stuff. It's harder to actually build new characters, because it's really difficult to find a LEGO set these days that just has people, and they're always really expensive. The LEGOs I have are probably about twenty years old now. But I'm definitely more into creating stories than actually building them.
Still, LEGOs were a really big part of my childhood.