My parents seperated first when I was about 8/9. They stayed seperated for about two weeks and then got back together.
Then when I was about 11, they started divorce procedings, and that was the beginning of 2 horrendous years for me and my brothers.
My parents hated each other at that point and lots of nasty things went on, in and out of court.
I told my dad that I wanted to live with him (so did eldest brother), and so then began a huge custody battle too. This invloved me, as a 11/12 yr old haveing to find my own legal representation to fight my corner, as the family mediators that were supposed to help me, completely ignored anything that I said about my dad.
Because of what I went through I made a HUGE effort throughout mine and xp's seperation, never to involve the kids in arguments, make them feel they had to take sides etc etc and try and keep it as amicable as possible. I didn't always succeed, but I am comfortable in the knowledge that my dc, although obviously upset by the whole thing, didn't go through what I did.
My mum once tried to give me advice on my seperation from xp, and I told her no offence intended, but she was the last person that i'd ask for advice on how to get divorced without wrecking your childrens lives.
She wasn't impressed with me, but it was true.