*1.1. Definition and Determinants of Division of Housework*

Housework is defined as the work needed to maintain a household, and can be distinguished into different activities [34]. Routine housework entails work that needs to be done on a day-to-day basis—such as cooking, washing dishes, cleaning, laundry [35]. Non-routine housework includes house repairs, garden work, and paying bills. There is a relative flexibility in terms of when these tasks need to be done and they are more discretionary [34]. Childcare can also be distinguished into routine versus non-routine care [36,37]. Routine childcare entails the physical aspects of generally looking after children, such as feeding, cleaning, regular bedtime activities. Non-routine childcare includes enrichment activities, such as, reading to, educating, and playing with children. Mothers usually carry out and are expected to carry out more housework and childcare, especially routine/physical housework and childcare. On the other hand, fathers do less and mostly carry out non-routine housework and childcare [37–41]. Needing to carry out routine housework and childcare can act as a greater hinderance to one's labour market participation as it represents a larger part of domestic work, with less flexibility about when it can be done. Thus, only when fathers take on more routine care and housework activities, can mothers be relieved of some of the pressures arising from balancing family and work [34,38]. Finally, one particular element of non-routine childcare that is important to examine during the lockdown period was home-schooling. As schools shut, parents had to home-school their children, with many parents spending two or more hours on these activities per day [42] adding extra childcare demands onto parents [43].

Several theories help explain how couples divide domestic work [44]. Time availability theory argues that the division of housework is rationally distributed depending on the amount of available time each member of the household has outside of their paid work. Relative resources theory argues that the division of housework is determined by the relative resources each partner brings to the relationship—i.e., those with higher education/income/wealth do less housework compared to those with lower education/income/wealth [45]. The 'doing gender' [46] perspective argues that it is the socially expected gender roles that determine the way couples divide domestic work. Namely, women do more domestic work because they are seen to be responsible for these tasks, while men focus on bread-winning because that is what is expected of them [39]. Thus, even when women earn more money, or work longer hours, they still end up carrying out more domestic work than their male partners [45,47].
