Mary Ann was the second of ten children of John Waymouth (Accountant) and Ann (nee Blackman).   Being the only daughter to survive childhood, she was required to help look after the household and family, and in later life, her parents.
Mary Ann was twelve years old when the family (parents and six children) emigrated from London to New Zealand.
Initially, the family lived in Freemans Bay, Auckland.   Later the parents moved to Dunedin Street, Ponsonby and Mary Ann lived in a house in St Francis de Sales Street that backed on to her parents' property.
On 22 September 1876, Mary Ann married William Buckby at All Saints Church, Auckland.   William was a mining engineer.   They had no children and William died in 1889.
Mary Ann's eldest brother's wife died in 1886 leaving a young family.   Mary Ann adopted the youngest child, Fanny Claudia Waymouth, who was then aged about four years.