All of this is a powerful argument for giving one's loved ones regular gifts while alive but leaving all of one's financial assets to charity on death.
Inadvertently, Bob created a powerful incentive for his own death. Most people would never see it that way but most people aren't his three lovely daughters.
...or his son in law, or his grandson.
I say it is a powerful argument for not telling your children or grandchilden your net value.
I hope the grandsons wife has some skills. I foresee her being a single mom some day, possibly soon. In fact, I wonder if AH's loyalty is stronger to his father or his wife and children? Because he has taken one heck of a risky gamble here.