Hi there Jeff - could you be seeing something more than is there? Essentially, from what you have reported, an alternative view is that you are saying the same thing to each other...how about using this - you could see it as an honest exchange between 2 people - which is good - could you 180 it by perhaps emailing to say:

"Well, it sounds as if D7 gets upset when she leaves you and when she leaves me - or an event like a switch from one of us to the other reminds her about the situation. Perhaps we could have a chat to think how we might deal with this situation so we can help her to deal with it?"

Jeff - even if your interpretation is actually correct - you could put a different spin on it to model a more productive/collaborative approach...

anyway - just an idea...

KBO - GFI


Me: 40ish
W: 40ish
Together: 20 ish years
Married: 10ish Years