Frank Joslyn Baum (who at times used the alias L. Frank Baum, Jr. (3 December 1883 – 2 December 1958) was the eldest son of L. Frank Baum, and the one of Baum's four sons who pursued his father's imaginative legacy most vigorously. His efforts in the realm of Oz, however, brought him controversy and estrangement from his relations. F. J. Baum's connections with Oz are manifold: An article titled "Corresponding with Frank Joslyn Baum" appeared in the Winter 1982 issue of The Baum Bugle.