Human fertility rates showed a marked decline in Western Europe from the mid-nineteenth century until the beginning of the twentieth century. The causes of this decline have been studied extensively, but no complete explanation to the observed patterns during this ‘First Demographic Transition’ has yet been given. Following recent literature, this study examines the fertility decision-making process at the level of the individual. In particular it focusses on the role of other people - specifically family members - in shaping perceived constraints and preferences regarding parenthood. Family members can increase or reduce offspring survival chances and fertility outcomes by providing resources and support, or through social influences as social learning, social pressure, subjective obligations and social contagion. The outcomes of this study show that family members influenced fertility outcomes in Western Europe during the first demographic transition. Their influence however varied depending on the type of kin and over time.