advise on paying out mortgage, page-13

Greg

It will not affect in in regards to tax at all and nor is transaction likely to become any of the ATO's business in itself. It is a gift from your father to you and nothing more.

If your number happens to come up, through a random audit or some other trigger and the ATO reviews your affairs they are likely to want to know where the money come from to ensure it is not undeclared income of either you or your father. Otherwise there would be no problems in relation to tax.