Vocabulary size is a crucial early indicator of language development, for both monolingual and bilingual children. Assessing vocabulary in bilingual children is complex because they learn words in two languages, and there remains significant controversy about how to best measure their vocabulary size, especially in relation to monolinguals. This…

This study aimed to adapt and validate the Word Complexity Measure (WCM) for Persian-speaking toddlers. The WCM is a tool for assessing phonological complexity, originally proposed by Stoel-Gammon. The study was conducted in two phases: (1) adapting the WCM parameters to the Persian language and (2) conducting a validation study with 60…

While it is established that parental "wh"-questions, as a high-quality language input, are associated with child language outcome, less is known about the role of children's "wh"-questions in their language development. This study examines whether children's "wh"-questions during a dinnertime conversation are…

The Mayan language Mam uses complex predicates to express events. Complex predicates map multiple semantic elements onto a single word, and consequently have a blend of lexical and phrasal features. The chameleon-like nature of complex predicates provides a window on children's ability to express phrasal combinations at the one-word stage of…

In this article, we present an analysis of the complexity of grammatical constraints and their impact on early language acquisition of inflectional morphemes in Malayalam. We use the natural speech production data of two monolingual children acquiring Malayalam between the ages 1;9-2;10 and 2;3-3;0 and three bilingual children acquiring…

Toddlers with smaller vocabulary than expected for their age are considered late talkers (LT). This study explored the effects of characteristics of words on vocabulary acquisition of 12- to 24-month-old LT children compared with an age matched (AM) and a vocabulary matched (VM) group of typically developing peers. Using the…

This study examines whether children acquiring Tseltal (Mayan) demonstrate a noun bias -- an overrepresentation of nouns in their early vocabularies. Nouns, specifically concrete and animate nouns, are argued to universally predominate in children's early vocabularies because their referents are naturally available as bounded concepts to which…

A growing body of research suggests that fine motor skills (FMS) are associated with language development. In this study, we examined 76 children aged 3-6 years assessing the link between language and FMS. Specific measures included receptive and expressive vocabulary, oral narrative skills, and various fine motor tasks. Hierarchical linear…

Few studies provide information on the reliability and validity of parental report instruments when assessing the language skills of pre-school-aged children. This study investigates the internal consistency and concurrent validity of the parental report instrument, the Finnish version of the Communicative Development Inventory III (FinCDI III),…

The inflectional diversity of parents' speech directed to children acquiring Dutch was investigated. Inflectional diversity is defined as the number of inflected forms of a particular lemma (e.g. singular, plural of a noun) and measured by means of Mean Size of Paradigm (MSP). Changes in the inflectional diversity of infant directed speech (IDS)…

Although a considerable number of studies have shown D(eterminer) elements, i.e. determiners and pronominal clitics, to be particularly vulnerable to impairment in monolingual children with Developmental Language Disorder (DLD), little is known about the use of appropriate or/and grammatically correct referring expressions in the children's…

A 7-year longitudinal study was conducted as part of the French national cohort ELFE (N = 1095). The aim was to identify how and why early language skills at 2 years might predict later literacy skills assessed successively at 5, 7, and 9 years (LitSk5y; 7y; 9y). Using one and the same model, we also examined the relations between literacy skills…

This research investigated whether observing beat gesture and hearing contrastive accenting with novel words enhances their learning in early childhood and whether these effects differ by sex in light of sex differences in the pace of language development. Fifty-three 3- to 5-year-old boys and girls learned pairs of novel words with contrasting…

Heritage language (HL) speakers seem to diverge from monolingual speakers in the acquisition of syntax-discourse interface phenomena. However, most of the studies reporting this finding do not make any distinction between different types of syntax-discourse interface structures. Therefore, it is an open question whether these structures are…

In a changing society where the roles of fathers and mothers in caregiving are becoming more equal, the role of the father in early language development has also changed. We aimed to study associations between paternal factors and early vocabulary development in boys and girls. In a longitudinal cohort study, we examined the growth of expressive…