sob (v.)
c.1200, "to cry with short breaths," probably of imitative origin, related to Old English seofian "to lament," Old High German sufan "to draw breath," West Frisian sobje "to suck." Related: Sobbed; sobbing.
sob (n.)
late 14c., from sob (v.). Sob story is from 1913. Sob sister "female journalist who writes sentimental stories or advice columns" is from 1912.