They basically pulled themselves up by the bootstraps." But that's an incomplete picture, because what's more important is that they had factors in their lives that helped to influence their agency, or their specific capacity to actually overcome the obstacles that they were facing and navigate the system given their circumstances.
Básicamente agarraron el toro por los cuernos, pero esa es una imagen incompleta, porque lo más importante es que tuvieron factores en sus vidas que ayudaron a influir en su capacidad de acción o su capacidad específica para superar realmente los obstáculos que enfrentaban y navegar por el sistema dadas sus circunstancias.