Rosalie Mackenzie Poe—like the Allans, her foster parents added the family name when they had her baptized—made no travels, wrote no poetry, and had no real prospects for an independent adulthood. Like Poe, Rosalie was raised in Richmond. Although Rosalie outlived her brothers, dying in a church home when she was sixty-four years old, apparently she never progressed beyond the developmental age of a twelve-year-old. By all accounts, she was a plain, simple, affectionate sister who actually played with their little cousin Virginia, who was fifteen years younger. She loved and baffled Poe, who would often try to figure out why she wore hairstyles and dresses so out of fashion.

It was Rosalie Poe—and not her brothers—who came with a mystery attached. Who was her father? There's certainly some doubt it was David Poe, Jr., who was apparently gone from the family a year before Rosalie was born. The inference is that Eliza Poe's “compromising letters” that came into John Allan's hands suggest an alternative paternity. The rumor at the time was that the handsome young actor John Howard Payne was the father. Payne was performing in Boston with Eliza at the time, but he spent the next twenty years on the London stage. If he was the father, it's possible he never even knew. His theatrical career eventually included writing for the stage, but Payne has two more remarkable high points in his successful life. He was the first American consul to Tunis and he wrote that enormously popular sentimental hit song, “Home Sweet Home.”