This paper examines evidence for a nonlexical influence on children's repetition of real words. We investigate the extent to which two computational models of auditory repetition can simulate the performance of 68 children aged between 5 and 11 years-old when they are attempting to repeat familiar words. Both computational accounts were derived from Foygel and Dell's ("J Mem Lang" 43:182-216, 2000) semantic-phonological model of picture-naming. Results showed that a dual-route model in which a lexical and a nonlexical route work together to repeat familiar words (Hanley et al. in "Cogn Neuropsychol" 21:147-158, 2004) provided an accurate simulation of children's repetition, whereas Foygel and Dell ("J Mem Lang" 43:182-216, 2000) single lexical-route model under-predicted performance. The only exception was the repetition performance of 5 year-old children, which was over-predicted by the dual-route model. It is argued that at 5 years of age, some children have available both a lexical and a nonlexical repetition route but the output of the two routes does not summate when real words are being repeated. Some young children may lack the attentional skills that would enable them to co-ordinate the activity of the lexical and nonlexical repetition routes.