Australians do u know wat will happen?

my best friend has 3 young children and has been claiming a single parent pension, she had a falling out with her father who has been ringing centrelink saying that her ex has lived with her ince 2000 wich is a load of crock, he does come there and see the kids and sometimes sleeps over and they have had but he does not support her financial and infact she is struggling financially, im scared for her, will she go to jail if they believe she is frauding them, she has no criminal history. just worried for her and the kids.