clearly indicates that _two boys_ is a weak instrument in the context of Albania. For this reason, it will not be used in the second-stage estimation.

Lastly, the first-stage estimates of the over-identified model in column (7), which uses both _two girls_ and _two boys_ as instruments, also indicate that having two girls increases the number of children by 0.43 on average and this result is statistically significant at the 1% level. On the contrary, having two boys does not seem to produce an effect on the number of children and the result is also statistically insignificant, proving to be a weak instrument once more. Thus, the over-identified specification is neither a good candidate for the second-stage estimation.

As a whole, the first-stage results in Table 7 confirm once more that Albanian parents have a strong preference for having sons. In particular, having two girls increases the likelihood of having an additional child, while having two boys seems to have no effect on fertility after controlling for several covariates. Even though the instrument _same sex_ seems to have a positive and statistically significant effect on fertility, it does not mean that Albanian parents prefer to balance their children’s sex-composition because this variable is only capturing the variability generated by _two girls_ . Therefore, the second-stage estimation will be based mainly on the exogenous variability of the instrument _two girls_ . The _same sex_ instrument will be used only for comparative analysis.<sup>27</sup>

# **6.2 Main Results: OLS and Second-Stage**

This section presents the main results of the effect of fertility on parental labor-force participation. The OLS and second-stage results are estimated separately for the mothers and the fathers because women and men in Albania differ substantially in the type and amount of labor they supply. Tables 8 and 9 report OLS estimates in column (1) and two sets of IV estimates (i.e. _same sex_ and _two girls_ as instruments) in columns (2) and (3) for the sample of mothers and fathers, respectively.<sup>28</sup> All the specifications include the same set of control variables as in Table 7. The upper panel of these tables reports the estimates for the different measures of labor force participation (e.g. _worked in last 7 days, work off-farm, work on-farm, self-employed_ ), while the bottom panel reports estimates for _hours worked per week, second occupation_ and _monthly labor earnings_ .<sup>29</sup>

> 27The corresponding first-stage estimates for the sample of fathers presented in Panel B of Table 7 are almost exactly the same as the ones for the sample of mothers.

> 28The first-stage specifications of columns (4) and (6) in Table 7, which use _same sex_ and _two girls_ as instruments for fertility, are the ones selected for the second-stage estimation because these are the ones that proved to be the strongest instruments after controlling for covariates.

> 29The variables presented in the bottom panel of Tables 8 and 9 such as _hours worked per week, second occupation_ and _monthly labor income_ are only available in the Albanian LSMS surveys, but not in the Albanian DHS survey. For this reason, the sample of mothers is reduced to 4,862 observations and the sample of fathers to 4,530 observations. The first-stage estimates for these reduced samples are very similar to the ones shown in Table 7, but very slightly smaller in magnitude. Once again _two girls_ and _same sex_ prove to be valid instruments for fertility, while _Two boys_ seems to be a weak instrument. The first-stage estimates for these samples are reported in Table A-4 of the Appendix.

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