As an Australian, I think Australia is a great place for someone who might want/need a second chance or a fresh start. As Australian citizens, the sons (and possibly the mother too) would be entitled to immediate access to the public health system as well as social security. While it is not what it was, if the family landed in Aus with next to nothing (and no jobs) then the social security would ensure they would be OK. I believe the the social safety net is also pretty good in the Netherlands so maybe there were other reasons for them leaving. (And yes FromGermany, the great outdoors are also appealing too
) If SS's possessions were pawned it is probably likely that the twins have known poverty during their lives as it takes a certain amount of desperation to look at the ring of a dead woman and see $.
I think there was a trigger for them to leave Europe and perhaps we should be looking at unsolved crimes in Holland in the month leading up to their departure. Maybe VS's and MS's records are clean but are there some mysteries in their old neighborhood?
Is it possible the mother knew something was up and fled to Australia, possibly even demanding that the twins split up and that MS has to go live someplace else. Maybe this was the rift. Musing...