Thank you all for your responses!! This helps a lot. If anyone has another 2 cents to add, feel free!
Becky,
When you say that a family will have had to filed their I-600A, do you interpret that to mean actually have their 171-h back, or just have submitted the I-600A application, done fingerprints, paid the fees, etc?
Shannon,
Yes, there might be an unexpected addition to the Benson family! Not for certain yet though.
ps- I never got the email pic of your little one.