... ."mom was talking about canceling the plans to go to MN if she misses anymore school and he doesn't want her to miss out on that opportunity". Do you think that is appropriate? Does anyone have any other ideas in case it doesn't work, or if its really not an appropriate response on our parts?
I am not sure. It depends on how "ill' she will feel tomorrow. If he does say something like that, I would re-word it in a more positive way:
"Your mom and I talked about that trip to MN, and we very much want you to be able to go. For that to happen, we need to keep your absences to a minimum from now on. I know you don't feel that great, and it sucks having to go to school when you don't feel like it... .Is staying home worth missing out on that trip?"
Also, what will you do if she DOES miss too many more days? Are you going to cancel the trip, or are you going to go anyway? If you are not ready to follow through, I wouldn't mention it. It would be what's called intermittent reinforcement. Something that makes the behaviors much worse in the long run.
Here's a quote on that taken from the discussion on extinction bursts:
https://bpdfamily.com/message_board/index.php?topic=85479.0Intermittent reinforcement: slot machines use this. They pay out on irregular schedules. You never know when you will win, but you know that if you keep pulling the handle that sooner or later a pay out will occur. It may happen on the third pull or the twentieth pull, but you will win if you keep trying. The fact that you KNOW that you will eventually win, keeps you hooked into trying.
What does this mean? If you tell your partner that you won't answer the phone while at work, and they call you 20 times, and you answer on the 21st attempt, you have just inadvertantly given them intermittent reinforcement. Now they know that if they bug you enough, that you will always eventually respond. This actually escalates the behavior you are trying to stop. They believe they can win if they just keep pulling the lever, even if they go broke trying, they will keep at it. The more irregular and unpredictable your response to them, the more they will keep trying. It is the combination of hoping they will get their way and not knowing when it will happen that keeps them trying.