Joslyn Stanton Baum (1908 – 1982) was L. Frank Baum's first grandson.
Born on 14 July 1908, he was the son of Baum's oldest son Frank Joslyn Baum and his first wife Helen Snow Baum. Baum Senior dedicated his next Oz book, The Road to Oz (1909), to the baby. The author's inscription in the copy of the book he gave to his grandson was later printed as "A Short, Short Oz Story."
As a child, Joslyn Baum bore the nickname "Tik-Tok." His younger brother was Frank Alden Baum.
In 1940 Frank Baum married his third wife, the former Margaret Turner, who was born in 1907 — so that Joslyn Stanton Baum had a stepmother only a year his senior.