In this study, we investigated which componential skills can be distinguished in the second language (L2) development of 140 bilingual children with specific language impairment in the Netherlands, aged 6-11 years, divided into 3 age groups. L2 development was assessed by means of spoken language tasks representing different language skills organized into 4 categories based on prior research. Factor analyses were consistent with this system, identifying 4 types of componential skills included in our original assessment battery: (i) speech production/phonological memory; (ii) auditory perception/phonological conceptualization; (iii) lexical-semantic skills; and (iv) morphosyntactic skills. Structural equation modeling showed the 4 types of componential skills to be reasonably stable over time. Moreover, empirical evidence for a lexical bootstrapping effect was found in that children's syntactic development at the age of 8 years could be predicted from their level of lexical-semantic development at the age of 7 years.