Jo Cafarella (the boy, 9-years old) lived at 39 Warren Street, in Somerville, Massachusetts with his sister Lena (at right, 10-years old). They are working with their cousin Mary Lazzaro (center, 13-years old), who lived at 17 South Street. No record on the little girl in the foreground.

Very few boys of the time worked at crochet, but according to Hine little Jo had been crocheting for two years. He also has a very spiffy bow-tie, don't you think?
Nearly all of these urchins were discovered in the photography archives of the Library of Congress (and available without copyright restrictions online). Otherwise, urchin photos will be credited to the appropriate photographer with a link to its source (unless they come from my own collection of photographs from unknown photographers). If there is ever a copyright concern, do not hesitate to contact me.