Abstract
The number of older siblings a child has is negatively correlated with the child's verbal skills, an effect that is well known in the literature. However, few studies have examined the effect of older siblings’ sex, of the age gap between siblings, of having foreign-speaking parents, as well as the mediating role of parental interaction. Using data from 12,296 children (49.3% female) from the French ELFE birth cohort, we analyzed the effect of these characteristics of the siblings and their family on children's expressive vocabulary measured using the French MacArthur-Bates Communicative Development Inventory. Children's vocabulary at age 2 years was negatively associated with the number of older siblings (−0.08 SD per additional sibling), and this effect was partly mediated by parental interactions. In analyses restricted to children with one older sibling, the vocabulary score was negatively correlated with the age gap between the target child and their older sibling. The vocabulary score was not correlated to their sibling's sex, contrary to the result of a previous study. In addition, the effect of the number of siblings was less negative in foreign speaking families that in French speaking families, suggesting that older siblings might partly compensate for the effect of having foreign-speaking parents. Overall, our results are consistent with the resource dilution (stating that parents have limited resources to distribute among their children) and inconsistent with the confluence model (stating that a child's cognitive ability is correlated to the mean cognitive ability of the family). Research Highlights: Our results are consistent with the resource dilution model and inconsistent with the confluence model The negative effect of the number of siblings on expressive vocabulary is partly mediated by parental interactions Larger age gaps between a child and their older sibling are associated with lower expressive vocabulary score.
| Original language | English |
|---|---|
| Journal | Developmental Science |
| DOIs | |
| State | Accepted/In press - 2022 |
Bibliographical note
Funding Information:The Elfe survey is a joint project between the French Institute for Demographic Studies (INED) and the National Institute of Health and Medical Research (INSERM), in partnership with the French blood transfusion service (Etablissement français du sang, EFS), Santé publique France, the National Institute for Statistics and Economic Studies (INSEE), the Direction générale de la santé (DGS, part of the Ministry of Health and Social Affairs), the Direction générale de la prévention des risques (DGPR, Ministry for the Environment), the Direction de la recherche, des études, de l’évaluation et des statistiques (DREES, Ministry of Health and Social Affairs), the Département des études, de la prospective et des statistiques (DEPS, Ministry of Culture), and the Caisse nationale des allocations familiales (CNAF), with the support of the Ministry of Higher Education and Research and the Institut national de la jeunesse et de l’éducation populaire (INJEP). Via the RECONAI platform, it receives a government grant managed by the National Research Agency under the “Investissements d'avenir” programme (ANR‐11‐EQPX‐0038 and ANR‐19‐COHO‐0001). This work has received further support under the program “Investissements d'Avenir” launched by the French Government and implemented by ANR with the references ANR‐17‐EURE‐0017 and ANR‐10‐IDEX‐0001‐02.
Publisher Copyright:
© 2022 John Wiley & Sons Ltd.
Keywords
- confluence model
- language development
- parental interactions
- preregistered
- resource dilution model
- siblings
ASJC Scopus subject areas
- Developmental and Educational Psychology
- Cognitive Neuroscience