Access to social security benefits is generally restricted to people who are Australian permanent residents or citizens residing permanently in Australia. This 10‑year qualifying residence requirement aims to ensure that only those people who have established a long‑term connection with Australia are able to access Age Pension and Disability Support Pension. The 10‑year qualifying residence period must include a period of five years continuous residence in Australia.
所以是拿到PR以后的十年，之前以其他签证类型居住的时间是不算的。
感兴趣的朋友可以看一下这是 social service department的原文，链接如下
http://www.dss.gov.au/about-the- ... -residence-criteria
另外，不知道你朋友的父母领取的是什么，如果是age pension，那一定是centerlink搞错了，但是也有可能领取的是别的福利，比如newstart allowance,那个是可以的，如果他的父母不到 age pension age且符合其他条件的话,