Releasing a son/daughter from Shiva and all other mourning dinim

Question:

A parent has been ignored by his children without explanation for almost 10 years. The parent has a non-lethal thus far cancer, but nevertheless a very serious illness.No visiting, no speaking, complete withdrawal from being a child to both parents. The children have never called or inquired regarding his health in almost 10 years, nor have called about anything else. Moreover, and more painfully, the children have withheld their children (the parents grandchildren) and do not allow them to see or speak or be near their grandparents. Again, for no cause. There is no abuse here whatsoever. The parents have tried and tried to ask for a reconciliation, but have always been either ignored or rebuffed.
Question: May the parent write a final instruction (צוואה) stating that these children may not attend the funeral, sit shiva for the parent, nor have any dinim of mourning, including saying kaddish? May the parent forbid them from ever coming to his gravesite?
Thank you in advance.

Answer:

It is clear from your question that you are very hurt and pained by what your children have done to you, besides for being sever insulted by their actions. What makes the situation worse is that you don’t even know the reason for it. Before getting to the halachic technical answer, you would be well advised not to do such a move. Although right now it seems like the situation will not change, it is still possible that later they might just have a change of heart, and you would be causing yourself unnecessary frustration and anger, that you might regret later on. You don’t have much to gain by instructing them about this, except for letting out your frustration and anger, getting back at them, and sending them a message, but you may be the one to lose out most as a result. If you leave them with this, you have shut yourself out of their life, and it will only make things worse. Instead, you can write them in the final instructions how upset you are at their actions, and that it caused you tremendous anguish. This might ignite a change of heart by them and they might regret what they did, and possibly do things for you that will help you in the world of truth.

From a halachic angle, regarding shiva and aveilus, these are halachos that they must keep because you are their relative, and the Torah and chazal obligate these practices when any close relative passes on, and neither you nor they have the mandate to decide not to keep it. Regarding saying kaddish, coming to the funeral, and coming to the graveside, these are things that are done solely for the benefit of the departed, and you can be mochel them that they are not obligated to do it, however these things are also not your property to forbid them from doing.

Therefore, from a practical and halachic angle, it is not something that is advisable for you to do.

May H-shem send you a refuah shleima, and arichus yamim, and also a yeshua from this painful situation so that you should have peace and nachas from your whole family.