What is the name of Poe's older brother?

Poe’s older brother was William Henry Leonard Poe, usually known as Henry Poe.

Born in Boston on January 30, 1807, Henry was the eldest of the three Poe children. Edgar was born in 1809, followed by their younger sister Rosalie in 1810. After their mother, Elizabeth Arnold Poe, died in 1811, the children were separated: Henry lived with relatives in Baltimore, while Edgar and Rosalie were raised in different Richmond households.

Henry traveled at sea before returning to Baltimore, where he worked and wrote poetry and short fiction. His story “The Pirate,” published in 1827, drew on Edgar’s youthful romance with Sarah Elmira Royster. Henry’s experiences and literary interests appear to have influenced Edgar, who sometimes used the French-inspired alias “Henri Le Rennet,” derived from his brother’s name.

Henry died in Baltimore on August 1, 1831, at age 24, after suffering from tuberculosis and related health problems. Because Edgar’s foster brother was John Allan, readers sometimes mistake Allan for Poe’s older brother, but Henry was his biological sibling.