nothing mattered but the data-and what strange data it was they needed

Like mother, like child: Intergenerational patterns of age at first birth and associations with childhood and adolescent characteristics and adult outcomes in the second generation.
Hardy, Janet B.
Developmental Psychology, Vol 34(6), Nov 1998, 1220-1232. http://dx.doi.org/10.1037/0012-1649.34.6.1220
Special Section: Longitudinal Studies of Intergenerational Continuity and the Transfer of Psychosocial Risk.

A 30-year follow-up of 1,758 inner-city children and their mothers in the Pathways to Adulthood Study revealed significant associations in transgenerational timing of age at 1st birth between mothers and their daughters and sons. Intergenerational age patterns were associated with the children's family and personal characteristics during childhood and adolescence and self-sufficiency at age 27–33. Continuity in teenage parenthood was associated with family and personal characteristics unfavorable for optimal child development and successful adult outcomes. Delay in 1st parenthood to age 25 or older was associated with significantly greater odds of more favorable environmental and developmental characteristics and greater adult self-sufficiency. The authors concluded that age at 1st birth of both mothers and children contributes, but in subtly different ways for daughters and sons, to the children's development and adult self-sufficiency.