Here's the situation/background. My grandfather on my dad's side is too ill to travel. He lives about 4 hours away, and if we gave him the option, he'd drive up here to see me but honestly, his health is just too risky. So My aunts take care of him, when he's not in the nursing home for something serious. My aunts have already said they are both trying to come up for the wedding, along with one of my cousins (she's 15)
Now, my oldest cousin (will be 20 when the wedding happens) is pregnant with baby number 2 and due 3 weeks before the wedding. I don't know how to bring up the situation with her! I had assumed she wouldn't be coming anyway, because of the custody arrangement she and her ex have in place (no travel over a certain distance or some stupid shyt like that).
I just don't know how to bring it up. I considered messaging her of FB and just flat out saying, "You and the kids are more than welcome to come up, but I will totally understand if you can't or don't feel up to it." Is this OK to do? I don't want anyone to have hurt feelings or feel left out, but I do understand- coming from 4 hours away, with kids, planning for a hotel stay, etc., etc. Blah.
How would you handle it?

Mom to D.A (11.09) and 3 beautiful angels (06.08, 03.11, 07.12)