When their infants were 6 months of age, mothers were assessed for self-efficacy (low, moderate, and high illusory control) and knowledge of infant development to determine their impact on mothers' behavioral sensitivity and affect during a feeding task at 9 months (N=70). Mothers' sensory sensitivity to digital images of infants' negative and positive expressions assessed in a signal detection task at 6 months was hypothesized to mediate this relation. Mothers with moderate illusory control exhibited greatest behavioral sensitivity and positive affect. Low knowledge was associated with reduced sensitivity for mothers with low illusory control only. When viewing the negative expression, mothers with moderate illusory control and high knowledge exhibited greatest sensory sensitivity, and mothers with high illusory control and moderate/high knowledge were least sensitive. Although sensory sensitivity was not a mediating variable, its relation to both illusory control and subsequent maternal measures during feeding was informative. Although greater sensory sensitivity predicted more sensitive behavior and more positive affect, only for maternal affect was the relation independent of illusion of control effects.