I’m a bit puzzled. According to “The New England Historical and Genealogical Register,” Vol. 11 (July, 1857), which has an extensive study of the Lane family papers, Job and Sarah had only one child and it died in infancy (pg 241). The reason Elizabeth is listed under Sarah is her given date of birth and the known dates of the marriages of the two wives.

"Genealogical Dictionary of the Early Settlers of New England," James Savage, 1860-1862, v III, pg 52