Higher proportions of births outside marriage and more family breakdown indicate that children experience increased diversity of family circumstances at birth and during childhood. While England/Wales and Norway have many similar features, there are distinct differences in social and welfare policies. This article compares children’s experiences in the two countries in relation to these policies. Emphasis is put particularly on the impact of consensual unions. Children are the statistical unit and data from surveys and national statistics are compared. In both countries there is considerable risk of family dissolution in the case of children born into consensual unions, but the more so in England/Wales than in Norway. Even though the rate of extramarital births is much higher in Norway than in England/Wales, the corresponding rate of family change is lower. The article suggests that behind parental break-up lies an old pattern of social stratification masked as family change.