Tatham, Samuel William and Jane

Jane Tatham was the witness at the weddings of two of my ancestors in Masterton New Zealand. Firstly in 1901 at the marriage of Mary Dora Walker (nee Tatham) to George Marshall and then her daughter Marion Walker to Thomas Morris in 1903.
I am researching the Tatham family and have not come across any family link to Samuel William Tatham and Jane (listed as a trainer of Parkvale Wairarapa, New Zealand in 1905). There is a Jane Tatham who died in Tauranga on August 13 1937 who I assume is the same person. She was a widow aged 83 and according to her obit was born in Collingwood, Victoria, Australia and left a son and daughter.She is supposed to have come to NZ when about 13 years old.Maiden name unknown.
With the Tatham name being an uncommon one - and this association at two weddings I am really curious to know who Samuel William Tatham was and where he came from.