Where do stories come from?

It wasn't until last year that I found out my grandpa Gill's best friend growing up had been a Muslim, and that his family had fled India two years after Partition (the separation of India and Pakistan) because of continuing religious tensions that had been made far worse by Partition.
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Lately, I've been wondering why I didn't hear that story until recently, about how I could easily have missed that story altogether if I hadn't asked my grandfather about his memories of Partition, and also about why we hear certain stories and miss others.

I think these questions are particularly pressing across cultural contexts. I've had trouble telling certain stories not grounded in common American culture in my graduate workshops, because many readers are resistant to cultural material they don't know a lot about yet. My grandfather, perhaps, had a similar difficulty sharing certain stories from his early life during his later life in America: knowing that people might not understand probably affects us all as day-to-day storytellers even more than it affects me as a professional writer.

I asked my grandma when she found out about my grandpa's childhood best friend, Shaffee, and about similar details of Grandpa's childhood. She told me that some things had come up before they were married and during their early marriage, but the story about Shaffee and many other details came in the late 1960s, after my grandfather's first trip back to India.

Being here, she felt, he'd often been focused on figuring out life in this new world. Going back not only triggered memories, it also made him want to share information about people's current status that required him to go back and explain in much richer detail how things had been before he left.