Her father, Daan Brouns, was sheltering in a homemade air shelter with his family when the Lancaster crashed nearby. The resulting explosion destroyed their home.
Young Daan and his brother Harrie rushed to the scene to see if he could pull out any survivors.
While he couldn't do anything for the three dead crew, he managed to rescue some of the crew's personal items.
At great risk, he hid from the arriving German soldiers a suitcase that contained maps, navigational tools, a document stamped 'secret', and the personal belongings of a 27-year-old audit clerk from Wellington, Flying Officer Horace Callow.
He kept the suitcase for the rest of his life, but never spoke about it.
Ria Schmieder-Brouns took it upon herself to unravel its mystery.
In 2003, she helped get a stone memorial to the dead airmen erected in her small village. Every year they hold a remembrance event.
And this year, Sergeant Roche's niece Sharnee McGill will take part after being tracked down to her Gold Coast home by Ms Schmieder-Brouns.
Ms McGill is visiting her uncle's grave today to scatter her mother's ashes beside her beloved brother.
"That is going to be hard to do, but very special," she wrote on her Facebook page.
Tomorrow, a Lancaster bomber will do a fly-over of Heythuysen.
"This memorial will always remind us of all these men ... and my father, who forever will be and remain my hero," said Ms Schmieder-Brouns.
On the night of July 21, 1944, an Avro Lancaster bomber MK1 of RNZAF Squadron 75 left Mepal airfield in Cambridgeshire, England.
Its mission was to bomb an oil refinery in Homberg, Germany.
But as they crossed southern Holland, they were hit by Nazi fire.
The plane caught fire and began to hurtle towards the ground.
It was a "descent in terror", Bombardier Warrant Officer John Burgess later wrote.
Keeping a cool head that belied his 21 years, Roche heroically decided to stay at his pilot controls.
English flight engineer Sergeant Joseph Armstrong and Callow also remained to try for a safe crash landing.
It gave the rest of the crew time to parachute into the night sky.
Tail gunner Flight Sergeant Keith Smith, a 21-year-old clerical cadet from Auckland, was shot out of the sky and killed.
The parachute of English RAF volunteer reserve, wireless operator Sergeant Jack Barson, did not open. He also died.
Roche dropped some bombs from the flaming, wounded Lancaster before it smashed into the ground behind the Brouns' house. Roche, Armstrong and Callow were killed.
Burgess parachuted down and hid in a haystack. German soldiers were about to bayonet it when he gave himself up. Burgess remained a prisoner of war until May 26, 1945.
Mid upper gunner, Flight Sergeant Bill McGee landed unspotted and slept in nearby woods. That night, he heard two more planes crash.
The next morning he made contact with members of the underground resistance. McGee reached Paris on August 25, 1944 - the day it was liberated by the Americans.
He died in Whangarei in 1986, aged 76 years old.