She started her international beach volleyball career in 1997, playing tournaments around the world with her sister Debora. Between 1997 and 2000 they were Dutch national champions. They won the silver medal at the European Championships in Rhodes 1998 followed by a bronze medal in 2000. They also participated at the 2000 Summer Olympics, where they lost both of their matches, eliminated in the second preliminary round by Lina and Petia Yanchulova, also sisters. Following the Olympic tournament Debora quit volleyball. Rebekka continued to play and found a new partner in Marrit Leenstra. In 2001, 2002 and 2004 another three Dutch national titles were won. In Basel 2002 Kadijk/Leenstra reached the final of the European Championships. They lost this final, earning a silver medal. Their main achievement came in 2003 when they won the World Cup meeting in Lianyungang (China). They qualified for the 2004 Summer Olympics, but met little success there. After the Olympics they split up. Kadijk's next partner was Merel Mooren and, like Rebekka's earlier teams, Kadijk/Mooren were nearly unbeatable in their own country. In 2005 and 2006 they became Dutch national champions. In both 2005 (Moscow) and 2006 (Scheveningen) they reached the final of the European Championships. They lost on both occasions, earning two more silver medals. In 2007 they won the final of the German Masters in Hamburg, their first European Tour Tournament win.