Answers are grounded in this paper and cite their sources.
Deborah Lowe Vandell, Kathy Shores Wilson, Nola R. Buchanan, Peer Interaction in the First Year of Life: An Examination of Its Structure, Content, and Sensitivity to Toys, Child Development, Vol. 51, No. 2 (Jun., 1980), pp. 481-488
No takes yet. Share an insight, caveat, or question.
Vandell et al. (1980) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: