It looks possible that he had another son Edmund Downes Hoare (later changed his name to Edmund Treadaway Hoare) who was born on 15th November 1837 with his mother being Jane Hill.  However it has yet to be established that the father of Edmund was also the father of this JTH.  Possibly a 1441 census would do the job: in 1837 this James and Jane were living at 114 Compton Street, Clerkenwell.

If the two JTHs are the same person, then there is a descendant living in the Germany with a dau in London who are related to our Turners of this day.

In 1841 there was this small family in Compton St, Clerkenwell:
James Hoare aged 35 (to nearest 5 yrs), a metal dealer, born in Middlesex
June or Jane Hoare aged 25 (to nearest 5 years), also born in Middlesex
Son Cumand(???) aged 3, born in Middlesex.
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Family Search has this marriage for 1832:

groom's name: James Treadaway Hoare
bride's name: Jane Hill
marriage date: 27 Aug 1832
marriage place: St. Bride Fleet Street, London, England
indexing project (batch) number: I02224-3
system origin: England-EASy
source film number: 568043
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