This study investigated the development of English two-member onset #sC clusters in Spanish-English bilingual children with phonological disorders. Data from 30 children were analysed in terms of correct and incorrect productions, implicational relationships, and possible groupings according to the sonority index of the second member of the cluster. While a great deal of variability occurred both within and across children, a number of general findings did occur. Sonority sequencing was found to be relevant in accurate renditions. Also justifiable was the binary grouping of /s/+[-continuant] vs /s/+[+continuant]. With regard to reduction patterns, the predictions of factorial typology were found to be useful.