This mystery flower popped up in my garden, and I had no idea what it was. During a garden tour I hosted someone who works at the MN Landscape Arboretum identified it as Indian pink. It's a native plant, but not to Minnesota. It ranges only about as far north as Missouri. I have no idea how it appeared in my garden. The only things I had planted in that area were some whorled milkweed, snowberry and dogwood shrubs.