I am not sure if you have lots of information or are looking for more information or only living descendants

Possible birth and baptism from IGI Extracted record
BEHENNA James
Birth 29 Nov 1821
Baptism 9 Jan 1822 St James, Westminster, London ENG
Father Isaac BEHENNA
Mother Mary Ann BREAY
A spelling variation with Ellen's surname on the marriage reg

Marriages Dec 1843
BEHENNA James Poole Bloomsbury 1/ 82
MOLTON Ellen Elizabeth Bloomsbury1/82
1851 Census
Living at 14 Oval Street, St Mary's Lambeth HO107/1873
BEHENNA James Head Married 29 years Railway Clerk b. St James Middlesex
BEHENNA Ellen Wife Married 26 years b. St James Middlesex
BEHENNA Mary Ann Dau 8 years Scholar b. St Anns Middlesex
BEHENNA Ellen Elizabeth 7 years Scholar b. St Anns Middlesex
MOULTON Mary M.I.L Wid 58 years Dependant on her son b. St Martins Middlesex
MOULTON Augustus B.I.L. Wid 28 years Carver & Gilder b. Lambeth Surrey
HIETT Hannah Serv 17 years Domestic servant b. Henley Oxfordshire
Their arrival in Victoria in August 1852 on the
Mary Harrison Port B Fiche 005 Page 008 and 007 for James.
POOLE James 30 years
POOLE Ellen 27 years
POOLE Ellen 9 years
POOLE Mary Ann 8 years
I guess you have found this
http://www.unisanet.unisa.edu.au/research/condon/teachers/Teachers.asp?TeacherID=1410So there are the following marriages and it is descendants from these marriages you are seeking
EVERETT Charles Ellis Status not known 22 years Father Charles EVERETT
POOLE Mary Ann 22 Status not known Father James POOLE
8 Nov 1864-11-08
Place Christian Chapel Mitcham Ade 60/45
and
HILL Nathaniel 23 years Status single Father John Victor HILL
POOLE Ellen E 24 years Status single Father James POOLE
13 Jul 1873
At the residence of Mr Broadfoot Thebarton Yat 96/162
A couple of deaths
POOLE James
25 Nov 1890 68 years Status Not known Relative Not recorded
Residence Adelaide Died at Port Adelaide PtA 190/86
POOLE Ellen Elizabeth
4 Aug 1903 78 years Status Widow Relative James Behenna POOL [Deceased husband]
Residence Parkside Death Place Parkside Ade 296/116
Hopefully a descendant will find your request.
Cheers
Cando