Hi
If you mean permission to take children he needs to sign a statutory declaration saying he is the father and agrees for child to migrate to austrailia with mother and become an ausrailian citizen has to be witnessed/signed and sealed by solicitor/public notary. He needs Id as passport/driving liscence.
If he doesn't agree you would need to go to court, I don't know anything about this but someone on here might.
Good Luck
Brenda
