@dee0829
Hi Dee, I'm assuming you meant this re: 2 years PR before sponsorship from: http://www.border.gov.au/Trav/Brin/Pare
You might be eligible to apply for a <b class="Bold">parent category visa</b> if:
you have a child who is an Australian citizen, an Australian permanent resident, or an ---eligible New Zealand citizen
your child has been living in Australia lawfully for at least 2 years before you lodge your visa application
you have a sponsor
you meet the Balance of family test criteria
you meet health and character requirements.
This visa is different from a Tourist 600 visa, you can definitely bring your mum to AU on a tourist visa as it doesn't have restrictions. Just provide a letter to authorities for your mum as a visa requirement stating that you would want her in for a visit.
The Parent Category Visa is a Temporary Resident Visa as opposed to a Tourist Visa which just lets you visit at a specific date range be it 3, 6 or 12 months.
With a tourist visa, you can extend your stay by applying for another tourist visa even when you are in Australia, provided that you don't have an 8503 condition imposed in your valid tourist visa.
re: http://www.border.gov.au/Trav/Visa-1/600-