This is a really problematic situation. Courts are loathe to do anything which would scare people away from reporting abuse or neglect. The best you can do is to cooperate with DYFS, remind them of the prior false allegations, and clarify to them the nature of your relationship with your mother. It really is sad that your mother would do this if the allegations are merely a way to hurt you, because they end up hurting the children.
There is no way to stop someone from making reports to DYFS.
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