Cross-country comparisons show that family policies supporting the work-family combination are related to higher fertility in industrialised countries. We argue that within each country, there is a dominant norm about the care of small children, linked to the shape of family policy, that influences individuals' fertility decisions whatever their gender roles attitudes and practices. We compare western Germany and France, which have different family policy and child care contexts, and also different fertility levels, but exhibit similar attitudes and practices towards gender roles as measured in surveys. Using qualitative data (62 interviews), we show that in each national sample, most individuals manage to agree with the national norm about child care, on top of their varying attitudes towards, and practices of, gender roles. These national norms about child care shape fertility decisions, independently of the provision of child care. In western Germany, where mothers are seen as the best child care providers, women who want or need to work prefer to forgot having children rather than using other possible sources of child care. In France, where child care is seen as best when shared, individuals find child care solutions allowing women to work, even in cases where no institutional care is available.