My best friend is dating my cousin which is also a really good friend of mine. This is my bff's first boyfriend and since I have had a lot she turns to me for advice. Her and my cousin are in a fight and they are both asking me for advice. I don't want to take sides but I really think I should help them. Should I get involved or just lay back and let them work it out themselves?
If I do get involved what should I tell them?

It's not taking sides if you're honest with each of them about the things they tell you about. Try not to give each person private info you've heard from the other person, and DON'T let them play games with each through you.

It would be better for them to work it out themselves, but you can offer feedback when they ask that is essentially pointing each of them to respect and honor the other person in the midst of the fight.

The problem with many fights is often the EXTRA bad things that are said and done during the fight that has nothing to do with the issue. Tell them to fight fair, stay on topic, and NOT throw stones. It's hard to have a true "blow up" if at least one of the parties in the disagreement is at least trying to stay calm and civil.

Now if you can get them BOTH to stay calm and civil and stay on topic, then at least they have a chance to settle the fight more quickly, and on their own. Good luck.