We report two children, suffering from idiopathic partial epilepsy, who started to present, in the same period of time, with epileptic negative myoclonus (ENM) in one lower limb and fecal incontinence (FI). Polygraphic recordings showed that ENM was associated with paroxysmal activities distributed over the vertex region. Both ENM and FI disappeared when ethosuximide treatment was started. We hypothesize that, in our patients, ENM in one lower limb and FI depended on a transitory impairment, caused by epileptic activity that altered the functionality of nearby cortical areas, located in fronto-mesial regions, involved in the control of the muscular tone of the lower limbs and of the pelvic floor muscles.