C185 Genealogy 3 of the Cold Side of Lengchuan in the Northern Circle

Grandpa had said it was taken when he and Grandma returned home on the twentieth anniversary of their marriage, but he hadn't told me about the other three people in the picture, just that they were relatives. But how could Auntie Reiko recognize me? In the fifteen years I lived with my grandfather, my grandfather had never brought me to Hokkaido. She recognized me on what basis