Does this count as cutting off kinship?

Hi everyone, first post here. I’m a revert (important to consider this when talking about my family).

Growing up my father had to cut off 2 of his brothers due to them speaking very poorly about my mother, disabled sister, and us as a family in general. One of them has remained cut off because he constantly speaks negatively about us behind our back to other family members. But the other one has attempted to come back into our life a few times, with us believing him, and him even taking me on holiday when I was 14. However, he has now cut us off again and been speaking poorly about us with the other brother.

As the only Muslim in the family, am I obliged to speak up and re-tie these connections between myself and either of those uncles, or am I excused considering what they have done?

JazakAllah khairan 🙏