IT recently came to light that an older relative who is no longer alive did this to my wife when she was young. Is it appropriate to tell her parents that this happened, or should it be well enough left alone so as not to cause anger and waves since he is already deceased.
Hmm... :unsure:
What the victim (your wife) wants is what should be given absolute priority.
If she wants others to know, including older relatives *supporters*, then by all means speak up. It's so overdue and justified that what HER feelings are be given voice and action.
However, she should be in a state of recovery whereupon she is built up enough to withstand any would-be lying and abusive reactions from his *supporters*/her detractors.