Maree and Albert Rizk, who were returning to Melbourne after a month-long holiday in Europe, died Thursday when MH17 came down in eastern Ukraine, Australian media reported.
Maree's father is married to a member of a Queensland family that lost husband and wife Rodney and Mary Burrows on MH370 when it disappeared en route from Kuala Lumpur to Beijing on March 8, Rodney's brother Greg Burrows told AFP.
Burrows said he did not want to make a statement on behalf of the Rizk family, but said: "We've got no ill feelings with Malaysia Airlines."
"Nobody could predict this one and nothing's been proven on the first one, so there's nothing there.
"We are still waiting for answers on the first one."
Flight MH17 airline was carrying 298 people, including 28 Australians, when it came down over rebel-held territory in Ukraine, with US officials saying it appeared to have been shot down by a surface-to-air missile.
Rodney and Mary Burrows were returning from a holiday abroad with friends when they boarded MH370 in March.
"They were beautiful people and we loved them dearly. Hopefully it was quick for them," a neighbour, who did not want to be named, told reporters at the time.
No trace has ever been found of MH370, which is thought to have crashed into the southern Indian Ocean.