I would agree if there were any other evidence of Julia as a child either Leonard or Artist. Julia appears as a member of the household in a single census and does not show anywhere else including "The Wentworth Genealogy; English and American". The others shown in the household appear in other records and their relationships are well established. My supposition is that Julia was a relative who was taken into the family but I can not find her elsewhere.
Leonard was my paternal gg grandfather.