Gertrude of Northeim daughter of Henry, Margrave of Frisia (1091–1160) Parents Gertrude of Brunswick Henry, Margrave of Frisia Children Adela von Orlamünde Beatrix von Rheineck Sophia of Rheineck Siblings Dietrich III. von Katlenburg Otto III of Northeim Richenza of Northeim Henry II, Margrave of Meissen Partners Otto I, Count of Salm Siegfried of Ballenstedt