In this ongoing project we investigate a fundamental aspect of human nature: evaluating others’ actions as praiseworthy or blameworthy. We do so in a closely coordinated, multi-laboratory, standardized study aimed at replicating the helping/hindering finding reported by (Hamlin, Wynn, & Bloom, 2007). Using a video-taped version of the original puppet show, labs from around the world will collect data from infants between the ages of 5.5 and 10.5 months.


Kelsey Lucca, Francis Yuen, and Kiley Hamlin


For a detailed index of collaborators (+ institutions, countries, studies), check the MB collaborator dashboard:


Pilot data collection complete; Stage 1 Registered Report has received an In Principle Acceptance to Developmental Science (read the preprint); preparing to begin data collection


We encourage everyone who is interested in the project to contribute and/or contact the project leads by e-mailing: Kelsey.Lucca [at], francis.yuen [at], kiley.hamlin [at]

Please note that access to infants/infant lab is not a prerequisite.


ManyBabies Consortium (under review). Infants’ Social Evaluation of Helpers and Hinderers: A Large-Scale, Multi-Lab, Coordinated Replication Study.