We investigated the interrelations between chronological age, theory of mind (ToM), Yield (as a measure of individual suggestibility), memory and acceptance of experimental suggestion in a sample of children between 3 and 7 years old (N = 106). One week after participants interacted with ‘a Teacher’, they were asked to recall activities carried out with the Teacher (direct experience) and the contents of a story read to them by the Teacher (indirect experience). Data were examined with an analysis of developmental trajectories, which allows establishing the predictor value of socio-cognitive developmental factors regardless of participants’ chronological age. It also estimates predictor values in interaction with the age and determines whether age is the best predictor for performance. As in previous research, results showed that chronological age was the main predictor of memory performance, both for direct experience (i.e., activities performed) and indirect experience (i.e., contents of the story). However, ToM and Yield, together with participants’ ages, modulated their acceptance of the external suggestions received (presented only once, one week after the event). A turning point was observed at age 4.6. Below this age, the greater the mentalist skills (higher ToM), the lower was the vulnerability to external suggestion. Still, children below this age characterized individually as being suggestible (Yield medium or high) were more vulnerable to suggestion the younger they were. Thus, developmental socio-cognitive factors might modulate young children’s vulnerability to external suggestions, even if received only once.