Wow, Shel, and all of you who have these unexpected half-siblings or unknown children of your spouses/ex-spouses show up. What a challenge to process that info.
It sounds like this girl doesn't live anywhere near you, Shel, is that right? She's in Arizona and you're in MD? But that's the family your daughter has been living with? Ay-yi-yi. Does she happen to like this girl, anyway? I wish you patience and wisdom as you sort out what to do about this, if anything.
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And in other pregnancy news - I just found out I'm going to be a great-aunt once again! The nephew who got married in June has just announced to the whole world, via Facebook of course, that they are expecting. So yay! One more baby to make things for! I am really thrilled for them. They will be fantastic parents, I'm sure.