Beyond the first question: A Bayesian multilevel analysis exploring verbal scaffolding strategies among teachers, parents, and grandparents during shared book reading

Shared book reading (SBR) is widely recognized for promoting early language development, yet research has focused primarily on adult contributions while overlooking children's role in co-constructing these interactions. This study examined how teachers, parents, and grandparents scaffold learning during SBR in low-resource rural China, where grandparents frequently serve as primary caregivers due to parental work demands. Thirty-two preschool children participated in four SBR sessions: two with their primary caregiver (17 parents, 15 grandparents) and two with their classroom teacher (13 teachers), reading both narrative and expository picture books. We coded adult questioning, scaffolding strategies, and linguistic diversity, alongside children's response types and question-asking. Multilevel analyses revealed that parents resembled teachers in downward scaffolding and questioning but used fewer upward scaffolds and less linguistic diversity; grandparents provided simpler input with fewer questions and scaffolds overall. Strikingly, however, children asked significantly more questions during interactions with parents and especially grandparents than with teachers. These findings challenge deficit views of grandparents as less effective language partners and instead highlight their unique capacity to create conversational spaces that encourage children's question-asking and active participation. This study stresses that child question-asking emerged as a powerful yet underemphasized indicator of SBR quality. By centering children's participation and examining grandparents' contributions in context, this study advances an ecological perspective on early language development in low-resource settings.