As the grandparent you have a right to request orders that your granchildren spend time with you,
You have to follow the same process as you son and that is mediation and if that fails seek the courts assistance.
You should contact your closest family relationship centre. This is a free service provided by the Federal Government. Their website is
You can find your closest one on there.
The web-site also have alot of useful information and links to assist you.
Before going to court you must obtain a certificate from a family dispute resolution practitioner. You get this through the free service provided at the family relationship centres.
If you need to go to court then you will need to file an application in the Family Court or the Federal Circuit Court
http://www.familycourt.gov.au and http://www.federalcircuitcourt.gov.au
In relation to the messages she leaves you can use them in your evidence that she denigrates him.
You have a right to spend time with your grandchildren and the court recognises your rights.
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