Both of my parents are alive and in good health. While my wife's father recently passed away, her mother is in good health. Both sets of parents have accumulated a substantial nest-egg via IRA, 401k, savings, pensions, and Social Security benefits. Over the last year I have seen several articles dealing with proper methods to reduce estate, excise, income, and capital gains taxes as well as avoiding probate that would enable the aging parents to properly pass on their accumulated wealth with minimal tax consequence. The first thing you need to remember is that it is their money and they can do anything they want with it, including wasting it on an ungrateful Internal Revenue Service.
Some people spend their last years preoccupied with how to leave their money.
You won't change that with, or without, diplomacy. This would effectively eliminate the Federal Estate Tax. Not to mention improve the security of the surviving spouse. For people age 70 and over there is no limit. Neither private pension income nor qualified account withdrawals are considered earnings.