She emigrated with her parents and siblings to New Zealand in 1855 aged about 21.
Mr. Isaac and Mrs. Aroa and 3 children; M. A. Aroa and Mr Robert Aroa emigrated to New Zealand arriving October 23, 1855 on the ship Maori.  Nelson Examiner and New Zealand Chronicle, 27 October 1855, Arrived. October 23, ship Maori, 1,000 tons, Petherbridge, 107 days from London. Steerage passengers —
In 1857 she married William Broughan / Brougham  but the registration has her name as "Anne Eroa" instead of Mary Ann Aroa. Her husband's gravestone spells his name as Broughan.
Using searches on alternative spellings Mary Ann Broughan and Mary Ann Brougham, there are 3 possible matching children
Electoral Rolls for Broughan, resident in Kaikoura
1914 and 1919
She passed away in 1919.
She is buried with her husband William Broughan at Kaikoura Public Cemetery, Kaikoura, Canterbury, New Zealand 
The death occurred on Thursday of another of Kaikoura's pioneers Mrs M. A. Broughan, at the age of 85 years. The late Mrs Broughan arrived in New Zealand 64 years ago at the age of 21, and she had resided in the Kaikoura district for 52 years. Deceased was a kindly-disposed lady who was held in the highest respect by all who came in contact with her.- She had eight children. five of whom are loft to mourn their loss. They are Mr W. Broughan, and Mesdames T. Treloar, L. Akersten (Blenheim), D. Sweeney, and J. Brown (Dannevirke). The late Mrs Broughan's husband predeceased her by 18 months. 
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