Contributory Parent 143

kitel

I'm planning to apply for my mom's 143 visa. There are 4 of us siblings and my sister just got her permenent residency 190 visa. She's been working in Tassie for 8 months under employer visa (temporary visa). I'm PR and have been living ni Aussie for more than 2 years. My question is, do we need to wait for my sis to be PR for at least 2 years before we can apply for my mom's 143 visa? Does the minimum 2 years settled PR only apply to the sponsor (me) or to all children in Aussie? Maraming salamat in advance sa makakasagot.