T I'm probably playing amateur detective here and getting it all wrong BUT it seems like your XH suddenly want to spend a lot of time with your youngest D. Given that he is also going on about child maintenance do you think the two are connected?
I only ask b/c this is exactly what happened to me and now it is me who pays him maintenance whilst I get nothing at all from him.
Be careful
Me 43 XH 45 M 2.7.88 Divorce 7.10.09 Kids D20,S17 & D15