I find it interesting how both these women cut off grand children access to their respective murdered husband’s parents. On face value, it is very suspicious and seems stupid, petty and mean. My thoughts are, despite the suspicion and raised eyebrows such behavior draws, neither can/could deal with interacting with the parents due to overwhelming guilt it caused. I imagine they live in denial and repress their memory of their role, and they know they can’t do that when interacting with parents. It brings it all back. It is like rubbing their noses in the steaming pile of crap they try to forget.
Also probably fearful that the grandkids might innocently pass along some snippet of information that the murderers would find prejudicial. If this were truly a random act of violence by third parties, you would think the incident might bring everyone closer together, or, at a minimum, be a neutral. The fact that the “widows” cut off contact is surely an eye-opener.