Just chiming in here: I've two kids (D6 and D3) and no written agreement of any sort. Everything falls into place with W and we always abide by what we promise. She wants the S to be cordial and not only am I a reliable person, but I DB. ;-)
M39 D6 D3 (at S) S 2014-09 D 2016-09
"You can't start a fire sitting around, crying over a broken heart" - Bruce Springsteen.