The sketch corpus focuses on children aged between 2;0 and 4;0. In order to capture language development, recording takes place at five different ages: at 2;0, 2;6, 3;0, 3;6 and 4;0, allowing for divergences of ±2 months at each age. In order to capture variation, two children are to be recorded at each age. There are different possibilities for distributing children over the ages:

Longitudinal approach: If feasible, record the same two children at each age.

Cross-lagged approachCross-lagged approach: If the longitudinal scenario is not feasible, record the same children at two (or three) ages.

Cross-sectional approach: Otherwise, record 10 different children.