Sias and twin brother Robert are the sons of Tiaan Ebersohn, a centre who played for the and . They were born and raised in Bloemfontein, South Africa and schooled at Grey College. Here they climbed the ranks and eventually represented the Free State schools team at the national Under-18 Craven Week. They were chosen to represent the South Africa Under-20 team at the 2008 and 2009 IRB Junior World Championships.