My wife and my sister in law don't get along. Just about every time there is a family function, theres a prob.

Question

My wife wants to speak with her, but I don't think it would be good. I'd rather see her just control her actions and try to not do the things that cause arguments, or to not allow my sister in law to bother her so much.

Answer 1

Every family has at least one judgemental, sniping shrew who thinks it is her task in life to rattle and irritate everyone's nerves.
My brother-in-law's ex is one. I just made it a point to stay the heck away from her... they divorced soon enough.

The only person your wife has any control over is herself. If the SIL is baiting her, your wife needs to play "too dumb to take bait". Do not respond to taunts.