Got a Facebook request from my Ex's sister?

[Angela]

We broke up about a year ago, our relationship went straight down hill, and now I'm with somebody else. He tried calling me and we ended up fighting and we both ended up agreeing not to talk to each other anymore, his grandmother and aunt dont even like me. But now his sisters, more like his younger sister, are still trying to contact me. They've been friend requesting me and trying to talk to me through an app we have on our phones (Voxer). I haven't answered, I'm scared. Dont get me wrong I love his sisters they're great kids but I don't know if I should talk to them or not. What if they ask about what happened? I'm not sure if I'm emotionally prepared to answer them. What should I do in your opinion?

[b]

you should talk to them. seems like the ex's msg is coming from his sister. it might be important IDK