Processing sentences incrementally entails making commitments to structure (and sometimes role assignments) before all information in a sentence is present. Children in particular have been shown to have difficulty revising the initial structural commitments they make when these turn out to be incorrect (Trueswell et al., 1999; Hurewitz et al., 2000; Weighall, 2008; Choi & Trueswell, 2010; Anderson et al., 2011). While prior research has generally ascribed this to limitations in the development of children’s non-linguistic cognitive-control system, a precise account of how cognitive control limitations might lead to difficulty with incremental sentence processing is missing from the literature. In part, this is because existing research has focused on individual differences in children’s ability to exert cognitive control over their thoughts and actions. In contrast, this dissertation makes use of within-child variation in cognitive-control engagement to provide evidence that children’s domain-general cognitive-control system pushes them to rely more heavily on reliable parsing cues (and less heavily on unreliable ones) when the system is highly engaged. This conclusion brings together seemingly disparate results from child and adult conflict adaptation studies, where adults appear to adapt to conflict but children do not. Overall, it is concluded that cognitive-control engagement leads both children and adults to re-rank parsing cues to attend more to ones that are more task-relevant, but the criteria they use to determine which cues are most relevant can change with language experience.