Oh dear. You know, it's so hard when posting on a board like this to put in every fact, and every detail of a situation...
I am also divorced, with children from my first marriage. My ex and I have one of those rare and wonderful post-divorce relationships where we don't fight and argue, or trash talk each other to the kids ... and visitation is now, and has always been, a very open and very changeable thing ... especially now since the kids are older and more involved in after school activities and after school jobs. So, yes, our kids do make up their own visitation schedule, and that works for us. One kid will call and say "Hey dad, I have a dance on Friday, can I come next weekend instead?" and dad always says "Sure hon, I'll come get your sister this weekend and you can come next weekend." Or if they both have something going on one weekend, they'll call and ask if they can do the next 2 weekends in a row, but skip the "regular" visit. It's just a non-issue with us.
However, my husband's relationship with his exwife is very different. He tries to be a lot like me ~ very open and flexible, and he never forced the kids to come for visitation if they didn't want to, or if they wanted to reschedule because they had something else going on in their lives (a dance, a slumber party) ... why make a kid miss out on something like that, when it's so easy to just rearrange your parenting time with them? I understand that some parents drive many hours to see their kids every other weekend ... but when you live closer to your kids, why not accommodate their schedules when you can, so they don't have to miss out on the fun stuff?
Anyway...my husband understood his daughters' reasons for not wanting to go to visitation with their mom that day ~ so he told them to talk to her, and it was fine with him if they want to change days if that was ok with mom. Of course, when mom showed up (45 minutes early, I might add, which is why they were unable to reach her by phone), and then threw a complete hissy fit in the driveway, yelling such things at them as "What? You don't love me anymore? Is that it? You'd rather be here with your dad and his bitch than come spend a few hours with me? Is that what it is?? Fine, if that's the way you want it, maybe I'll just go home and kill myself, then you won't have to worry about coming to see me anymore!" Yeah...I'd really want to get into a car and listen to that for the next 3 hours. Their mother was prone to these kinds of outbursts, especially when she was drinking (which I thought might have been the case that day, but couldn't prove it) ...I didn't blame them at the time for not wanting to go with her that day. It was such an easy solution...such a small request from her children "Please mom, can't we just stay here today so we can get caught up on our school work, finish unpacking our things, and get settled in...but then we can come spend the whole day with you on Saturday or Sunday?" I would have granted that request if it had been my children.