I think you provide a very good roadmap to her

But we still don't know if the trust is part of the deceased's estate or not. If not, where does the child support come from? Even if the law and/or the trust allows court to invade the trust principal, but it does not necessarily mean that the court would indeed do it, especially when the trust does make the child a beneficiary and allow him to stay there for free.

As I said earlier, this issue is very complicated. If she thinks it is worth the money and efforts, the best bet would be a competent attorney. One thing for sure, it is not going to be cheap. Given what is at stake, I probably would not do it.