This study examines factors that influence readers' cognitive processing (i.e., inference generation) and the development of a mental representation of text: comprehension skill and working memory (WM). Elementary students (N = 61) participated in causal questioning conditions with narrative texts to examine text- and knowledge-based inferences generated when probed during versus after reading. Recalls were examined to assess readers' mental representations of texts after-reading and answering questions. Skilled comprehenders generated more goal- and subgoal-related text-based inferences during and after reading and included more original text information and less background knowledge in their recalls of texts than did less-skilled comprehenders. Skilled comprehenders with high WM also generated more goal-related text-based inferences than did those with low WM. Findings support and extend previous research regarding how readers struggle with inference generation and may further inform the development of causal questioning interventions to help improve struggling readers' comprehension of narrative texts.