Hello
I looked on My Heritage and have found the Holmes Family going back after William Thomas Holmes.
Here is what I found:
William Thomas Holmes Parents: Thomas Holmes (1852-1930) and Agnes (1849-1904)
William Thomas Holmes Siblings:
Edith Annie Holmes (1872-1963) married Neobard
Frederick Charles Holmes (1874-1958)
Agnes Eliza Holmes (1876-) married Cook
James Holmes (1877-1951)
Albert Edward Holmes (1879-1966)
Olive Alice Holmes (1882-1960) married Adams
Walter Reeve Holmes (1883-1883)
Harold Edwin Holmes (1885-1960)
Ellen B Holmes (1886-)
Lilian Rose Holmes (1888-1954) married Finch
Thomas Holmes (1852-1930) parents: James Botwright Holmes (1818-1871) and Maria Davy (1824-1910)
Thomas Holmes (1852-1930) siblings:
Rose Maria Holmes (1846-)
Emily Holmes (1848-)
John Holmes (1849-)
Mary Holmes (between 1857 and 1859)
James Holmes (1863-1948) quite a few pictures of James and his wife in Australia (where he moved to) can send another post with those pictures if you want.
Harold Edwin Holmes (1866-1948)
James Botwright Holmes Parents: Thomas Copping Holmes (1793-) and Mary.
Apparently James Botwright Holmes died on July 23rd 1871 in Oulton Suffolk and had a ''Poor Law Burial''.
Thomas Copping Holmes is the furthest I can see back on the Holmes side here is more information about Thomas: Christened April 3rd 1793 in Walpole, Suffolk and married Mary on the 7th Feb 1815 in Westhall, Suffolk. In 1851 he lived in Beccles, Suffolk.
Summary: Arthur Harold Holmes--> Thomas William Holmes --> Thomas Holmes --> James Botwright Holmes--> Thomas Copping Holmes--> Thomas Holmes-->
Just found a baptism record for Thomas Copping Holmes and it is under ''Non-Conformist Baptisms'', which is interesting.
His father is listed as ''Thos'' (Thomas) and mother Hannah.
From what I can see it seems like the Holmes' were mainly Grocers and Pork Butchers in the 1800s and then gradually became Tanners Carters and Printers and Tailors in the late 1800s.
Sorry if you already had all of this information, hopefully it helps in some way.
edit: James Botwright Holmes' wife Maria Davy's father was called Barnabas Lee Davy which sounds quite interesting so there could be something going back on the Davy's side.