The head of house is expected to arrange matches for his or her children and any unwed younger siblings. Betrothals and marriages can be part of a pledge of support, or to help arrange peace between rivals.
According to Stannis Baratheon, 'the surest way to seal a new alliance is with a marriage'. Most betrothals among nobility are to ally with another family, not for love such marriages of convenience are also common among the middle class and peasants.
