Breaking her public silence, Denise Stark said she thanked Rob Nicholson for the apology, which came in a morning phone call after days of questions in the House of Commons.
"I explained how our wounds had been re-opened since receiving the cheque," Stark said.
"He acknowledged how insensitive this was."
In October 2011, 10 months after returning from a seven-month tour in Afghanistan, Cpl. Justin Stark, 22, killed himself.
The family of the reservist with the Argyle and Sutherland Highlanders of Canada had considered his estate long settled when the cheque for one cent in her son's name — dated Feb. 28 — arrived from Public Works.
The cheque was marked "CF Release Pay."
Stark said she didn't believe the incident was malicious or personal.
Nicholson promised to take a look at a military board-of-inquiry finding that the soldier's death was not related to his experiences serving in Afghanistan, said Stark, her husband at her side.
"Wayne and I continue to be dissatisfied at the board's confident conclusion that Justin's tour in Afghanistan did not cause him trauma," his mother said.
Stark stressed there would be no financial gain in having his death linked to his military service.
"It only involves having the recognition that those who died in theatre also have."
Nicholson called the incident a "bureaucratic screw-up."
He also promised to investigate to see whether the same thing had happened to others with the aim of ensuring it did not happen again.
"The death of a child is tragic but a death related to war ... I just don't have the words to describe," she said choking up.
"Then add to that, a death by suicide — it just adds another layer to my grief."
Wayne Stark thanked Nicholson for taking the situation seriously, and New Democrat MP Wayne Marston, who raised the issue in the Commons.
"We also hope this will help to bring positive changes to the treatment of our veterans and the families of our fallen," he said.
In Ottawa on Wednesday, Treasury Board President Tony Clement accused a civil servant of making "a very insensitive and terrible error."
He said the individual involved "should come forward and apologize."
Donna Lackie, president of the Government Services Union, said this week the data and information used to create the Public Works cheque would have come from the Department of National Defence.
The department would have no way of knowing why the cheque was requested, or the background of the person whose name was on it, she said.
"It's not the first time a one-cent cheque has gone through," Lackie said.
The Simcoe Reformer reported that in 2011 that Stark spent much of his tour of duty working to secure the town of Nakhonay, a small village 15 kilometres southwest of Kandahar city squarely in the heart of Taliban territory.
Several tribunals were held to determine whether his death was related to his work as a soldier, with a preliminary finding that it was not related to his service, according to his mother.
Keven Ellis, a family friend who heads a motorcycle group that supports veterans, the North Wall Riders Association, said the already emotionally distraught mother had been "devastated" by the cheque incident.
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-With files from Terry Pedwell in Ottawa
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