Send it or not?

My wife and her sister have not gotten along in many years. I can't list all the issues but her sister has turned many of her former friends against her. Neither of them are acting like they want to resolve the issues and get to the truth. When my MIL died the funeral was ugly and I took an earful from each of them.
Wife wants to send her sister a letter stating all the ways she hurt her and how she didn't take care of her mom etc. I have not read it but she said there are only a few bad words in it. I know that it can't be positive.
I told her not to send it because nothing good can come of it and she got pissed at me.

What do y'all think?

Do not send.

I often find myself writing long posts, then deleting them. Sometimes it feels good just to have written it down. Instead, encourage your wife to start an amusing blog like this one: http://mil-millington.com/ <--Things my girlfriend and I have argued about.

If you have nothing nice to say... shut tf up. That's what I'd tell her.

I wouldn't.

Nope. Bad idea.

Voicing her opinion in a conversation would be good but saying the same thing in a letter seems like long term trouble.

Agreed bad idea. It would just make the situation worse.

If you think it's bad now... It's going to just get worse when she sends it. Burn it!

I've heard of family that has done this (sent a letter). Everyone will hear about. It will NOT turn out well. If their relationship is so shattered that they don't even talk, or email, and a letter is the chosen method of choice, you might consider asking her why she is even bothering at all. If you have to go out of your way to shit on someone, you usually deserve being shit on just as much.

Ugh, now I'm thinking about instances of my own personal family drama and just getting pissed off. Tell her to knock it off post haste. There is a difference between being right and just wanting to feel good about yourself.

Send it! And get video. [Sofa]

Another don't send. Face to face is better and if neither wants to resolve the issues, so be it.