Spracherwerb (Schriftsprache) ; Language acquisition (written language) ; Kindersprache (Schriftsprache) ; Child language (written language) ; Schrifterwerb (psycholing.) ; Written language acquisition (psycholing.) ; Follow-up study ; Sprachverständnis (Lesen) ; Textrezeption (Zweitspracherwerb) ; Text reception (second language acquisition) ; Reading comprehension ; Listening comprehension ; Kindersprache (pathol.) ; Child language (pathol.) ; Specific language impairment; SLI; Dysgrammatismus (Kindersprache) ; Dysgrammatism (child language) ; Handicapped language acquisition ; Spracherwerb und neurologische Entwicklung; Language acquisition and neurological development; Sprache und Denken (Ontogenese) ; Language and thought (ontogenesis) ; Cognitive development; Language acquisition and cognitive development ; Morbus Down; Mongolismus; Trisomie 21; Down's syndrome ; Word deafness; Lexikalischer Zugriff (pathol.) ; Lexical access (pathol.) ; Word recognition (pathol.) ; Italian