Based on personal experiences and the guidelines outlined by the Department of Home Affairs, it can be challenging but sometimes possible to list a 21-year-old child as a dependent on a 186 visa. The key factor lies in demonstrating that the child is wholly or substantially dependent on their parent for basic necessities such as food, shelter, and financial support. It is not sufficient if the child is financially independent or able to support themselves. In cases where the child does not have a disability, the emphasis is on proving ongoing reliance. This often requires submitting clear evidence like bank statements, financial transfers, or official documents that show the child relies on parental support for living costs. Many Filipino migrants in Australia find it helpful to consult with a migration expert to navigate the evidence requirements and application process effectively. This proactive step can clarify any uncertainties and ensure proper documentation is submitted to Immigration. From my perspective, understanding the nuances of the family and dependent visa rules can greatly enhance successful visa outcomes. Also, keeping updated with the latest Department of Home Affairs policies is crucial, as changes can affect eligibility. Engaging with local migration forums and communities, like #PinoyInAustralia, provides valuable insights and peer advice. Remember, if a child over 21 does not meet dependency criteria, alternative visa options might be available. It's important to explore all migration pathways suited to your family's situation to secure the best chance of approval.