This week, Indians and Pakistanis have been showering the night sky with fireworks, singing patriotic songs, and memorializing national heroes in observation of their respective independence days (Pakistan’s was Thursday, India’s Friday).

But the 67th birthday of the antagonistic South Asian neighbors is also the grim anniversary of their divorce in the partition of 1947, when the British hastily and arbitrarily divided up the landmass formerly known as India along religious lines while leaving behind their former colony. The new borders created roughly 14 million refugees as Muslims in India and Hindus in Pakistan found themselves on the wrong side of the line, in what some historians have called the largest mass migration in human history. Estimates vary, but hundreds of thousands of civilians died in the process.

The legacy of tension has persisted for nearly seven decades, but one thing people on both sides of the India-Pakistan border have shared is the memory of partition's trauma. Now, though, people who were children in 1947 are in their seventies and eighties, meaning that these common memories are fading.

Guneeta Singh Bhalla hopes to preserve them. Born in India, Bhalla grew up hearing her grandmother recount fleeing Pakistan at independence. When Bhalla moved to the U.S. in middle school, she wondered why what her grandmother had called “an apocalypse” wasn’t covered in history classes alongside other important world events. On a trip to Hiroshima in college, Bhalla saw a memorial to the victims of the atomic bomb, with a collection of writings and videos from survivors. “That’s when it hit home,” Bhalla told me in an interview. “Watching these survivors talk about how their lives had completely turned upside down just for being at the wrong place at the wrong time made it real." She wanted to make partition real and understandable in the same way.