Over the two and half years that he spent in the Casa de Santo Antonio in Lisbon, Philippe Costantini followed the arrivals and departures of very young mothers, from their pregnancy through to the first years with their child. At the centre of this small community of teenagers and their new-borns, the exclusively female staff see to it that the residents, whose family situations are chaotic, obey the rules. Keeping off-screen an often-mentioned violence, the film focuses on the daily lessons in mothering. What then emerges is everything that cannot be taught and which creates a fine dividing line between having a child and becoming a mother.