Yes, that's what I would do, not bring it up. Maybe it's a question of semantics, I call it mindreading, you call it something else. Regardless, you don't know for sure she's going, you don't know when she's going, you don't if she's going with OM, you don't know what her childcare plans would be if she should go so-- I would call that mindreading. Dude, I know that this [censored] and it's a hard place to be but you need to unclench around this or the harder stuff is really going to kick your a$$. Stop thinking about this and GAL. The worse that could happen logistically is that you could have your S for a few extra days.
