Explaining the influence of younger siblings on firstborns’ understanding of minds in middle childhood: a longitudinal investigation of the mother- firstborn relationship

Paine, Amy ORCID: https://orcid.org/0000-0002-9025-3719 2017. Explaining the influence of younger siblings on firstborns’ understanding of minds in middle childhood: a longitudinal investigation of the mother- firstborn relationship. PhD Thesis, Cardiff University. Item availability restricted.

Preview	PDF - Accepted Post-Print Version Download (2MB) | Preview
	PDF - Supplemental Material Restricted to Repository staff only Download (696kB) | Request a copy

Abstract

This thesis focuses on the influence of younger siblings on firstborns’ understanding of minds in middle childhood. This topic was investigated in the context of the Cardiff Child Development Study (CCDS): a prospective longitudinal study of firstborn children and their families living in Wales, UK. As reported in Chapter 3, presence of a younger sibling resulted in an advantage on a second-order false belief task at 7 years of age. However, this advantage was only true for firstborns who experienced the birth of a sibling after their second birthday. It was hypothesised that the positive contribution of a younger sibling is mediated by changes to features of mother-firstborn conversation in dyadic interactions. To test this hypothesis, in Chapter 4 I described an expanded internal state language coding scheme for analysing mothers’ speech at 6 months, 21 months and 7 years. Mothers’ references to their 7-year-olds’ cognitive states positively predicted understanding of second- order false belief. As reported in Chapter 5, mothers who had a second child referred to cognitive states more than those with one child in middle childhood. Mothers’ variety of references to cognitive states partially mediated the association between presence of a sibling and firstborns’ understanding of second-order false belief. In Chapter 6, I investigated the families who experienced the birth of an early arrival younger sibling. Early arrival siblings were predicted by mothers’ symptoms of conduct disorder. Mothers who had an early arrival sibling present by 21 months referred to cognitive states less than mothers who did not. The findings in this thesis contribute to knowledge about the influence of younger siblings on the child’s development of theory of mind. The findings demonstrate the importance of examining how the arrival, and timing of arrival, of a younger sibling affects the dynamics of children’s other close relationships that influence children’s developing understanding of minds.

Item Type:	Thesis (PhD)
Date Type:	Completion
Status:	Unpublished
Schools:	Psychology
Subjects:	B Philosophy. Psychology. Religion > BF Psychology
Date of First Compliant Deposit:	5 September 2017
Date of Acceptance:	1 September 2017
Last Modified:	03 Nov 2022 09:15
URI:	https://orca.cardiff.ac.uk/id/eprint/104260

Actions (repository staff only)

Edit Item