In the commonly employed framework of family solidarity, kin availability and residential proximity are fundamental structural characteristics that shape contact, obligations and the giving/receiving of care. Within this framework, family support appears to have a pro-natal influence on women’s fertility, although evidence from low-fertility settings with a familistic tradition is still scarce. In this paper, we exploit a 10-year follow-up study starting around 2001 with geo-referenced data from the Longitudinal Database of the Andalusian Population to investigate whether Spanish women in the low-fertility setting of Andalusia are more likely to have a second child, and to have it sooner, if they lived in close proximity to parents(in-law) or siblings. To address these issues, we model the occurrence and timing of having a second birth as a function of locational nearness to kin after controlling for a set of individual characteristics and unobserved heterogeneity. The latter is explicitly introduced via Weibull survival and Accelerated Failure Time models with frailty. Our results indicate that the occurrence and timing of a second birth is positively associated with living close to mothers and siblings. In contrast, residential proximity to mothers-in-law and siblings-in-law is negatively associated with the occurrence and timing of a second birth. Results also suggest that such relationships are statistically significant among uniparous women with both low and high educational attainment. Our findings demonstrate the central role of kin relationships (mothers and siblings) for fertility and birth timing in Andalusia and highlight the key importance of spatial proximity to offset the relatively high costs of having a second child.