If you have a look at the National Archives of Australia website
www.naa.gov.au then click on "search as a guest" , then enter "Regina Kabar", you will get the following:
Zygmunt Kabar born 25.4.1920, Regina Kabar born 21.6.1924, Krystyna Kabar born 1/1/1944
The date of the record is 1949, and may be a naturalization record. Or they may have been 'displaced persons' emigrating to Australia. If so, it may contain the sort of information you want e.g. place of birth, parents, etc.
Click on "request copy" and fill in information then asked of you. If the material is available it will take about 4 - 6 weeks to appear on the website FREE OF CHARGE. You just have to periodically look up the original enquiry, and when you see a symbol stating that the record has now been digitized, you click on the symbol and the pages of the material relating to the Kabars will appear, and you can print them.