Yep, he might not do anything. How is that your problem?
Do you want him to come around? Will it upset you if he comes around?
It is possible for them to make arrangements to visit without you at an outside location, no? Couldn't they make plans to have lunch or dinner or go somewhere-- without you? Is there something logistical that would prevent that from happening?
I don't mean to be harsh but I encourage you to examine why you want to stick your fingers in this, even just a little bit.
Is your MIL expecting you to help resolve or facilitate her R with her own son? Does that seem ok to you?
