In a context of low fertility, a birth is a rare event in an individual’s life. In this short paper, the authors examine how the event is perceived in retrospect. Is the birth of a child seen as a key personal milestone? On the basis of an open question in the INSEE Life History survey on construction of identity conducted in 2003, the socioeconomic determinants of the perceived importance of a birth can be identified. Generally speaking, the most advantaged individuals are most likely to report that the births of their children were key events in their life. Trade-offs between the differing priorities of family and work, as well as the tensions of identity associated with the roles played in these two spheres are one suggested explanation for this. The unequal ability to express affect in words via an open question is another.