For all but a couple of the past 30 years, the 91-year-old has voluntarily written and directed a Christmas play, interlaced with Christmas carols, for the annual end-of-year production at Pukehiki Church.
Each play over the years has been a clever observation of present day life, mixed with the story of the birth of Christ, and the Pukehiki Church trustees all dutifully dress up and play their parts - often with hilarious bloopers.
Needless to say, her Pukehiki carol productions are a unique, joyous and fun celebration of the Christmas story that members of the community look forward to each year.
"I was inspired to write the first one back in the early 1990s because I felt that Christmas was a lot of things in the commercial world, and I wanted to make sure that people really encompassed the real story of Christmas.
"So I decided to write a little story that brought in things that were happening locally or around the world at the time, and bring the story around from that to the old story of Christmas and the kindness that everybody can give to each other.
"We just played our story out here in front of the congregation and mixed in some Christmas carols that fitted the story."
One of her favourite productions over the years was a play about a television news broadcast by the BBC - the Bethlehem Broadcasting Corporation.
The news broadcast covered the census that took place at the time of the birth of Christ, and reporters went around the congregation talking about the census.
"At the time, New Zealand was having its own census. I wanted to make it relatable."
Following last year’s production, the congregation was sad when Mrs Robertson said it would be her last.
"When I said I wouldn’t do another one, I had a few things on my mind.
"I had broken my shoulder and my vision is not what it used to be."
But about a month ago, inspiration struck and low and behold, out of the blue, she came up with yet another gem for a Christmas production.
"I live on my own, and lately I’ve been feeling like I just need something else for a diversion - something to keep me sane.
"So I decided to come up with a theme for a new play, and then all of a sudden, the title came to me.
"And once the title came to me, I just sat down one afternoon and it all just fell into place."
Before she knew it, she had completed her latest masterpiece.
As for the name of this year’s production, or what it is about, Mrs Robertson is keeping it more tightly wrapped than a Hollywood blockbuster.
Only she and the five cast members know anything about the play.
With tongue in cheek, she said anyone wanting to find out more was welcome to attend the "world premiere" at Pukehiki Church on December 15 at 7pm.
