He is married to Evyleen Duchesne Le Brun.
They got married on March 3, 1919 at Inyoni, Natal, South Africa.Source 1
According to the marriage certificate the couple was married at Mr G Getkates (Brides Uncle) house at Inyoni.
in 1919 Frederick was a Farm Manager at Amatikulu
"South Africa, Natal Province, Civil Marriages, 1845-1955," database with images, FamilySearch (https://familysearch.org/ark:/61903/1:1:KDCT-DGX : 10 March 2018), Frederick Jacobs and Evyleen Duchesne Le Brun, 03 Mar 1919; citing Eshowe, Zululand, Natal, South Africa; 02171; National Archives and Records Service of South Africa, Pretoria; 1,795,579.