Abstract: Fertility rates in Sub-Saharan Africa remain high and have declined more slowly than in other regions, even decades after the onset of the demographic transition. Rural areas consistently exhibit higher fertility than urban ones. Using data from the 2022 Kenya Demographic and Health Survey, I classify rural households into farmers and pastoralists and compare fertility outcomes across these groups. The analysis shows that women from pastoralist households have significantly higher fertility than those from farming households. I link this disparity to differences in property rights embedded within the two traditional economic systems. Motivated by these findings, I develop a single-sector model in which resource ownership is costly to maintain but children can help reduce this cost. The model demonstrates that under incomplete property rights, fertility is higher off the steady state compared to a setting with complete property rights, offering a theoretical explanation for the persistence of elevated fertility among pastoralist communities.