Your result
Australia — Reacquiring Lost Citizenship
Not eligible
You cannot resume a citizenship you never personally held, so this route is closed to you. But a parent who lost Australian citizenship raises a question worth pursuing, and the answer depends on when you were born.
If you were born while your parent was still an Australian citizen — that is, before they lost it — then a parent of yours was an Australian citizen on the day you were born, and you may have a claim to citizenship by descent in your own right. Their later loss does not undo that. If you were born after your parent's citizenship had already ceased, then no parent of yours was a citizen at your birth and descent does not reach you.
There is a further possibility if your parent lost their citizenship automatically before 4 April 2002: they may be able to resume it. That would not retrospectively help a claim of yours, because descent looks at the position on the day you were born, but it changes what is open to them and can matter for the rest of the family. Establishing the exact date their citizenship ceased is the first step for everyone involved.