This paper examines how culture determines within-couple gender inequality. Exploiting the setting of Germany's division and reunification, I compare child penalties of couples socialised in a more gender-egalitarian culture to those in a gendertraditional culture. The long-run penalty on the female income share is 30.9% in West German couples, compared to 18.3% in East German couples. I additionally show that the arrival of children leads to a stronger increase in the share of housework performed by women in West Germany and that women are responsible for a larger share of child care as those from the East. A specialisation index indicates that children only lead to a permanent (re-)traditionalisation in West German couples. A battery of robustness checks confirms that differences between East and West socialised couples are not driven by current location, economic factors, day care availability or other smooth regional gradients. The main findings are complemented with an analysis of time-use diary data from the GDR and reunified Germany comparing parents with childless couples. Lastly, I show that attitudes towards maternal employment are more traditional in West Germany, but the arrival of children leads to some convergence.
