I imagine that she is an Australian citizen, but I have no information to back that up. There is nothing in the media to indicate her family's ethnic background, but Droudis is a Russian/Slavic name - her family may be from the former Yugoslavia.
I also wonder about the ethnic background of Monis' murdered ex-wife - Noleen Hayson Pal. I believe she was also a US citizen, if I read a (not very clear) news article correctly.
