Originally Posted by WarChild

If she's not going to fight it, you just need documents drawn up. It shouldn't cost that much to have a lawyer do it. Really, very little. It gets costly when people fight it.

You might consider contacting your local University's Law college and asking if any of their students can help provide something at minimal or no cost.

The reason why this is important is you don't want this coming back to haunt you later. She decides a few years down the line that her new life isn't all it's cracked up to be, and hey maybe things would be better with her kids around more. She goes to a lawyer and now you're in for a fight with huge costs.