How do you deal with relatives who hold grudges against other relatives?

But the problem is not with you directly is against other members of the family who they do noteget along with? In this case the problem is them or the problem is the family?

I have two cousins who are siblings one is 49 and the other is 55. They both behave like immature people who has not grow up and put the past in the past with the family. These 2 particular cousins have grudges and are mad at some other couisns and even 3 of theri aunts, their mom sisters. The mother even if they do have disagreements with their sisters often and these cousins mom most of the time is not tactful as how to express things, they are still her sisters and she still talk to them but this aunt children are the ones who have disagreements and grudges with many relatives and other aunts and that has been happening for several years. This was caused due to some business all my aunts have and got in the way with family relations at the same time and that started many years ago and still up to this date these 2 cousins will never forget and let go even if the family business my aunts own still are in problems. These 2 cousins can't accept some of their own relatives sided with other relatives (who were right) in something related to the business and they do not sided with their mother (who was and is wrong)

The only relatives these cousins and their respecitve children do not hold grudges and still talk and we have a family relationship are me and my immediate family (my mom, my sister and my brother) cause for them we are their closest family relatives b uyt also they do know that me and my immediate family do talk to the relatives they hold grudges to as me and my family do not have problems with the others, the ones with the grudges are these 2 particular cousins.

Imagine that these cousins when planning birthdays or get togethers (Christmas, New Year get togethers) they only invite me and my family, they dont invite anyone else of the family

Updates
9 mo
not another aunt or their kids noone else. In the past and many years ago when it came to bdays and that type of celebrations the whole family was invited and at my house we always have a get together with all, not anymore. I have 2 aunts who came to visit us from the USA 3 weeks ago and they had not visited us for like more than 8 years, these 2 aunts while being here they had see most of all their nieces and nephews and their other sisters. Guess who they had no seen? Yep, these particular
Updates
9 mo
2 cousins, not because these aunts dont want to at the end, my cousins are these aunts niece and nephew but they are aware their own niece and nephew do not want to see them and that is the truth, these 2 cousins do not want to see their aunts since they came to the country to visit the family, they are not interested.
How do you deal with relatives who hold grudges against other relatives?
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