Re witness for Mary McKenna and John Turners wedding May 1876 looks like Charles Burson and Anne Burson.
Mary Sarah Blessington Death Certificate is Mary McKenna's daughter Mary Sarah Bourne. Mary Sarah married Thomas Bromhall Oct 1898 at Hughenden. It shows her parents as James Bourne and Mary McKenna. Witnesses David McLean and Winifred O'Connor.
Mary Sarah later went on to marry Saunders Blessington on 1st Mar 1920 Hughenden, Witnesses to marriage Ernest William Benoley and Theresa Bell.
Death of Mary Sarah. Informant Elizabeth Tait - Matron Emerald Hospital. Saunders Blessington, husband.
Death James Elliott. Pensioner 79 years died 26 February 1937, Eventide Home, Charters Towers
Born Dittisham, Devon 55 years in Queensland.
Parents Samuel Elliott. Occupation Seaman. No mother listed.
Marriages Townsville, Queensland 23 years, Mary McKenna. (This I believe to be incorrect. There is no Marriage recorded and on Mary's Death Certificate it states J. Elliott, no relationship, Living with deceased)
Children - Mary Sarah 57 years.
Medical - Lobar pneumonia, Senility, Cardiac Failure.
Informant - W.H. Berry Manager, Eventide Home.
Emma Theresa married a Patrick Fahey. I cannot find the papers on them at the moment, but she died 28th Oct 1917 in Queensland and shows mother Mary McKenna.
In regards to other children born to Mary McKenna I have found a birth 1885 James McKenna Queensland mother Mary McKenna no father listed and a Sabrina McKenna born 1886 mother Mary McKenna no father. I have not been able to find anything on them since their birth but will look further.