 His brother Carl was also a jockey who won the 1913 Kentucky Oaks but who was killed at age twenty-two in a racing accident on October 15, 1915 at Latonia Race Track.Jan Mosdorf

Jan Mosdorf (30 May 1904 - 11 October 1943), was a Polish right-wing politician, director of the nationalist organization All-Polish Youth ("Młodzież Wszechpolska", MW) and member of the far-right political party National Radical Camp (ONR).He also worked as a publicist, using the pseudonym Andrzej Witkowski.