According to several theorists, infants form mental representations and memories of their social-emotional interactions (e.g., Bowlby, 1969/1982), but very few studies have investigated these claims. Across two studies, I hypothesized that 10-month-old infants would form representations and memories of their social-emotional interactions. In Study 1, infants (N = 24) were familiarized to a positive and negative puppet and their representations and memories were assessed with visual-paired comparison (VPC) and forced-choice tests. Ten minutes after their interactions, but not immediately after, significantly more infants chose the positive puppet (17/24, p = .030). To better understand these results, I conducted another study in which infants (N = 32) were randomly assigned to be familiarized to either a positive and neutral puppet or a negative and neutral puppet. In the positive condition infants were more likely to choose the positive puppet immediately after (12/16, p =.038), but not 10 minutes after the interactions, whereas in the negative condition infants' choices were at chance - but older infants were more likely choose the neutral puppet (Mdiff = 11.50 days, p = .022). In both studies, no effects emerged with infants' preferential looking. Overall, the results indicated that infants' representations and memories of their brief social-emotional interactions were stronger for positive than negative interactions. Results are discussed with regard to existing theory and research and the negativity bias hypothesis.