perceived value of sons, irrespective of their economic value to parents. Across contexts, the common practices associated with son preference are patrilineal inheritance (inheritance through the male line) and patrilocal residence (co-residence with husband’s family after marriage). The more rigid these traditional kinship systems are, the less opportunity there is for girls to be valuable to parents. In these systems, sons cultivate the land, serve as primary care-givers for aging parents, and eventually inherit the land. Alternatively, daughters care for their in-laws after marriage. A daughter’s productivity is perceived as belonging to her husband’s household, and she is therefore deemed to be of little/no value to her parents (DasGupta et al. 2003; DasGupta 2010; Dyson & Moore 1983).<sup>5</sup> Traditional kinship systems that undermine the value of daughters versus sons are seen in all countries that have substantial sex selection. China, India, Korea, Albania, Vietnam, and the South Caucasus countries all have pre-industrial kinship systems that value sons more. As a reference, there are plenty of English language ethnographies of Asian kinship patterns (for China, India, Korea, see DasGupta et al. (2003); for Vietnam, see Guilmoto (2012c)). While English language ethnographies for South Caucasus are limited, the few studies that exist clearly document the predominance of male kin (Hayet 2002; Dragadze 1988; Ishkanian 2003). Moreover, recent qualitative studies in the South Caucasus region also illustrate the persistence of rigid patrilineal kinship systems. These studies find that for families in South Caucasus countries, sons have economic and symbolic value, that having a son is a source of security for mothers and a source of masculine affirmation for fathers, and that daughters, while helpful, are not as beneficial in the long-term as they prioritize their in-laws after marriage. While younger women in these countries are more likely to assert their desire to be economically productive, support parents after marriage, and inherit family property from their parents, there is still an overriding preference for sons (Yüksel-kaptanoğlu et al. 2014; Dudwick 2015).

The specific regions of the referenced countries above that have relatively higher levels of coresidence with sons are more likely to have higher levels of sex selection as well. For example, parts of north Vietnam have higher rates of co-residence with sons than south Vietnam, and correspondingly, north Vietnam has higher levels of sex selection than south Vietnam (UNFPA Vietnam 2011; Guilmoto 2012c). The persistence of these cultural norms could also explain why first-generation Chinese and South Asian immigrants in the West also tend to practice prenatal sex selection (Almond et al. 2013).

Comparisons with societies that have family structures that allow daughters more opportunities to contribute to parental households is also illustrative. For example, parts of Southeast Asia that have bilateral kinship systems also have normal child sex ratios. In bilateral kinship systems, sons

> 5 A recent study by Bhalotra et al. (2016) finds further support for the relationship between male-biased inheritance rights and sex selection as they examine how _changes_ in land rights impact child sex ratios. By exploiting variation in the creation of land rights by Operation Barga in the Indian state of West Bengal, Bhalotra et al. (2016) find that an increase in rates of tenant registration was associated with relatively higher survival prospects for boys particularly in families where the first-born was a girl. They argue when land rights are inheritable and primarily inherited by sons, there is an increased motive to sex select and ensure the survival of sons (because sons cultivate the land and provide support during old-age).

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