Lady Emily worked for the Te Taitokerau Maori Trust Board and was secretary of the New Zealand Maori Council while Sir Graham was chairman. During her time there she had a long involvement with Maori Wardens.
"She was a post, what we call a pou tokomanawa, for the Maori Wardens," said Mr Dargaville.
"In her prime day, when there were 88 Maori committees and 14 executive committees, there were up to 600 wardens. That was towards the late 70s and early 80s. She had strong advocacy for them. One person did that job and now we require sub-committees doing that job."
Mr Dargaville said her loss would leave a huge void.
New Zealand First's spokesman for Maori affairs, Pita Paraone, said Lady Emily helped put Maori issues to the forefront of the nation.
"Whether it was in the boardrooms of the New Zealand Maori Council and the Taitokerau Maori Trust Board, or the corridors of power or the highest courts in the land, Lady Emily was ever present to support the work of Sir Graham."
The funeral will be held tomorrow, at Te Paatu Marae, Kaitaia.