Twins Maya and Karla Dickason, and their 6-year-old sister Liane were found dead at their Queen St home last Thursday night.
The grieving father of three slain daughters has tonight spoken of his "three precious angels being ripped away".
A candlelit vigil is being held in Timaru outside the house where the three sisters were allegedly murdered by their mother a week ago.
Twins Maya and Karla Dickason, 2, and their 6-year-old sister Liané were found dead at their Queen St home last Thursday night.
Graham Dickason passed on a letter to be read at tonight's vigil.
He wrote "it is a loss I will carry with me for the rest of my life … my words are few".
"In this time of terrible tragedy and adversity I can only ask for prayer… for strength and for healing.
"Please also pray for my lovely Lauren for I honestly believe she is a victim in this as well.
"I have already forgiven her and I urge you in your own time to do the same … it is the key to healing this loss we have all experienced."
The family of the slain children sent tributes to be read on their behalf from South Africa, where they are still reeling from the devastating tragedy.
The girls' father, an orthopaedic surgeon, had been at a work function and arrived home about 9.40pm last Thursday to find the little girls dead.
His wife Lauren was unresponsive and rushed to Timaru Hospital, across the road from the house.
Lauren Dickason was treated and once in a stable condition on Friday night police charged her with murdering the three children.
She appeared in the Timaru District Court on Saturday morning.
Tonight's vigil, which started at 7pm, was organised by Hampers of Hope founder Jacqueline Harris.
Harris also stepped in to help the families of five Timaru teens killed in a crash last month.
She said tonight the wider Dickason family were touched by the gestures of kindness and support from the community.
She told media she had been speaking with Graham Dickason, who was moved by the plans for the vigil and that he and his family had input in the choice of readings and music.
People spoken to by the Herald said they were attending to remember the girls and show support for the family.
One woman said she was "still numb".
"It will take a while to really comprehend this, especially in Timaru," she said.
Timaru Hospital chaplain Reverend Alan Cummins is leading the vigil. Several hundred people are present.
Neighbour Jade Whaley will do a reading.
After her court appearance Lauren Dickason was remanded in custody to a psychiatric facility until her next appearance in the High Court on October 5.
The Herald cannot publish further details about the alleged offending due to suppression orders put in place by Judge Dominic Dravitzki.
Since news of the childrens' death emerged a steady stream of people have arrived at the scene - a property with three units leased by the South Canterbury District Health Board to house visiting medical staff - to drop off flowers, teddy bears and cards.
This afternoon there were more than 70 soft toys placed at the end of the driveway and dozens of bunches of flowers.
A neighbour told the Herald he had been out each morning to tidy up the makeshift shrine, moving the wilting flowers to the back and arranging the plush toys.
The children's bodies were removed from the scene last Friday afternoon and police finished their scene examination on Saturday evening, handing the property back to Graham Dickason.
A family member arrived in New Zealand to support him on Tuesday.
It is unclear if he has been back to the place where his wife allegedly murdered the couple's three little girls.
Graham and Lauren Dickason arrived in New Zealand last month with their daughters from Pretoria in South Africa.
Lauren Dickason is also a doctor.
The family completed two weeks in managed isolation in Christchurch before travelling to Timaru where Graham Dickason had a job with the South Canterbury District Health Board.
Just a week after they arrived in Timaru Lauren allegedly murdered the three children.
Detective Inspector Scott Anderson said the investigation into what happened to the girls was ongoing.
Alongside gathering relevant information for the prosecution, the Coroner may also open an inquiry.
"Once it's gone from the front page of the paper there is a huge amount of work that continues to go on as this moves through various prosecution phases," Anderson explained.
"From Thursday night through to Monday we had approximately 30 officers on the investigation," he said.
"As of Tuesday this has been scaled back to a team of about 15."
Funeral details for the slain sisters are yet to be shared.
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