I have a 6yo who came to us through foster care as a kinship placement(the one in my avatar with the shades on). i can see how sometimes things like this don't work out and i hope that if the people who are getting him can't do what's right for him that he gets sent back to you promptly. make sure that he and his worker both know that your door is open to him anytime he needs you. i would also add a leaf or something onto the quilt with your phone number on it so that he can always have it and can always reach you. that way it will be kind of hidden so that he doesn't have to share that it's there if he doesn't want to. i'm sorry you have to lose him again. i know how easy it is to become attached. we let our little man stay in contact with his old foster family, until his 'nana', as he called her, passed away. good luck and be proud, you have touched his life and changed it for the better, even if he can't stay with you he will always remember having a safe, loving home with you.