One of the things that is stressed in foster parenting is, "Don't get attached". As a foster grandparent, all I can say is, "Good luck with that". Had to say goodbye to three siblings (ages 6, 3 and 1) last night because this morning they went back into the system to be "re-homed".
The reasons for this step are complicated but basically the foster mom (my step-daughter) is expecting and was getting "spread too thin". I know the decision was a hard one and I totally support it... and my heart is broken. The kids have been a part of our lives for just under one year. I "got attached" to all three but the middle one (let's call her Fifi. I did.) really had me wrapped around her little finger.
So, you ask, Where are the birth parents? Good question. These three have four older siblings who live with their grandmother. Let that sink in. Seven children and the parents are too busy to take any responsibility for any of them, financial or otherwise. Grandma just isn't physically able to take on any more.
This helps. Thanks for being such a good listener. Hug your kids tight, if you have any. If you don't, hug someone else's.