Syntactic development; Morphological development; Morphologie (Spracherwerb) ; Syntax (Spracherwerb) ; Grammatical development ; Kindersprache (pathol.) ; Child language (pathol.) ; Specific language impairment; SLI; Dysgrammatismus (Kindersprache) ; Dysgrammatism (child language) ; Handicapped language acquisition ; Dual language acquisition; Bimodal language acquisition; Spracherwerb (biling.) ; Language acquisition (biling.) ; Bilingual language acquisition ; Coordinate bilingualism; Compound bilingualism; Dominanz (biling.) ; Dominance (biling.) ; Continuum (biling.) ; Language intervention; Children (speech therapy with) ; Speech therapy for children ; Second language acquisition in children; Kindlicher Zweitspracherwerb; Child second language acquisition ; Case (morph.) ; German ; Turkish