Former In-laws

[verum71]

Anybody have any experience with this one?  I've been struggling what to do with my former in-laws (Grandparents of my 3 kids).  My BPDx had effectively alienated all 3 of the kids against her parents and whenever their names (former in-laws) comes up when they are with me, there is always a very negative response and the kids clearly don't want to have anything to do with them. 
The problem is that my former mother in-law has been reaching out to me to get information and try to reach out to the kids.  This has been going on for the last several years (usually around birthdays, holidays, etc.).  One of the last times that my former mother in-law reached out to me, I clearly stated that I don't want to get in to the middle of this and if you are going to make any inroads with the grandkids you are going to have to do this through your daughter (my BPDx).  Things had been relatively quiet for awhile until the last month, when she is reaching out to me and wanting to try to get a hold of the kids.  To be honest, I have ghosted her with no response the last 3 times she has contacted me.  I am going back and forth between restating my previous response, which was "you gotta go through your daughter" - I'm struggling with a little Fear, Obligation, and Guilt - any feedback would be appreicated

[Poison Ivy]

How old are the children? I ask because I think generally that at some age, the decision about how much contact to have with family members should be up to the children themselves.

[Call Me Cordelia]

Say it again or just continue to ignore? Or are you considering giving in to her wishes?

Not knowing any of the backstory, you say your X has alienated the kids from them, the kids want nothing to do with them, and you've consistently refused to be the go-between and are currently, effectively, NC with them since you are not responding for three attempts now.

Seems to me a hopeless business. Would you consider simply blocking them?

[BeautifulCrazy]

In my opinion, these are relationships that are definitely not your business to maintain, or even be involved in, and your former MIL is seriously overstepping / being intrusive trying to get to the kids through you.
I totally agree with Call Me Cordelia. If former MIL is not getting the message, blocking seems like a nice tidy option that you shouldn't feel any guilt about. You have no obligation to your former in-laws.

[Lauren17]

I agree with the previous responses you've gotten. I did want to say that you're not alone in this. I'm in a very similar situation. My former in-laws have reached out to me multiple times with various tricks. I delete, decline or discard every one.
Have you read the book, Gift of Fear? The author tells a story of someone who is getting repeated, unwanted phone calls. After 21 unreturned messages, this person decides to call the stalker and ask him, again, to stop calling. The author states that the stalker didn't learn to stop calling. He learned it takes 22 phone calls to get an answer.
I think of that every time I choose not to respond.