Although many studies have investigated links between maternal employment and children's wellbeing, less research has considered whether the stability of maternal employment is linked with child outcomes. Using unique employment calendar data from the Fragile Families and Child Wellbeing Study (N=2,011), an urban birth cohort study of largely low-income families, this paper investigates whether the stability of maternal employment in early childhood (birth to age 5) is linked with child behavior and cognitive skills at ages 5 and 9. Employment stability (continuous employment over all 5 years, low levels of job churning, longer job tenure) was linked with less child externalizing behavior, but there was little evidence to suggest stability was particularly important for PPVT [Peabody Picture Vocabulary Test] and Woodcock-Johnson scores. Rather, for PPVT and Woodcock-Johnson scores, an increase in maternal employment in early childhood more generally was associated with higher scores.