Yes, it can be considered a form of abuse if a parent, who has knowledge of ongoing abuse, fails to protect their child or take appropriate actions to stop the abuse. This is often referred to as "failure to protect" or "failure to intervene."
In many jurisdictions, the law requires parents or guardians to ensure the safety and well-being of their children. When a parent is aware of abuse, whether it's physical, emotional, or sexual, and fails to take steps to protect the child from harm or seek help, they may be seen as complicit in the abuse and could be held accountable legally.
It's important to recognize that every situation is unique, and it can be complex when dealing with family dynamics and abusive situations. If you or someone you know is facing such a situation, seeking help from a trusted adult, a counselor, a social worker, or a support organization can be crucial in finding a safe and supportive way to address the issue.