http://en.wikipedia.org/wiki/K%C3%A4the_Kollwitz
Moltke d. J.Kollwitz lost her youngest son Peter on the battlefield [Flanders] in World War I in October of 1914. By the end of the year she had made drawings for a monument to Peter and his fallen comrades; she destroyed the monument in 1919, and began again in 1925. The memorial, entitled The Grieving Parents, was finally completed and placed in the Belgian cemetery of Roggevelde in 1932. Later, when Peter's grave was moved to the nearby Vladslo German war cemetery, the statues were also moved.