Graph theory ; Child language ; Spracherwerb und neurologische Entwicklung; Language acquisition and neurological development; Sprache und Denken (Ontogenese) ; Language and thought (ontogenesis) ; Cognitive development; Language acquisition and cognitive development ; Cohesion (text.) ; Kohäsion (text.) ; Coherence (text.) ; Kohärenz (text.) ; Text constitution ; Thematische Diskontinuität; Thematic discontinuity; Thematic progression