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Introduction Naps are known to benefit emotional memory consolidation in preschoolers, though improvement is not evident until the following day. The mechanisms by which naps aid emotional memory, and how they differ from those facilitating more neutral declarative memory consolidation, are currently unknown. In this study, we used an emotional storybook task to assess change in memory for emotionally salient vs. neutral events across a nap and overnight sleep. PSG was included to explore sleep physiology correlates. Methods Preschool children (n = 9; Mage= 43.2 months) were read a novel storybook featuring negative and neutral events. Memory of story events was probed through sets of multiple-choice questions and assessed at three time points: immediately following the story, following a nap or equivalent wake period (within-subject; counterbalanced; separated by ~1 week), and 24h post-encoding. PSG was recorded during the nap period and both subsequent overnight sleep bouts. Results Memory performance across time points was assessed via change scores. Recall of story events did not differ between conditions from immediate to post-nap/wake assessment. When probed the following morning, children better remembered events when a nap took place the day prior (F(1,7) = 8.848, p=.021). This delayed nap benefit correlated with time spent in NREM2 during the nap (r=.91, p=.017). No differences were found between recall of negative vs. neutral events at any time point or between conditions. Conclusion Our results show a delayed benefit of napping on recall of a storybook, though at present no preference for emotional events is seen. Time spent in NREM2 during the nap was strongly associated with our finding, likely reflecting the declarative memory benefits conferred from this stage. Further analyses will include overnight sleep physiology to explore differential enhancement between event types, and possible interactions with nap microstructure. Support This work was supported by NIH R01 HL111695.