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 ; Sprachfehler; Language attrition (pathol.) ; Language loss (pathol.) ; Sprachverlust (pathol.) ; Speech pathology ; Morbus Down; Mongolismus; Trisomie 21; Down's syndrome ; Pathologische Sprachproduktion; Pathological language production; Speech production (pathol.)