Never heard of siblings not being able to talk to each other, especially if the worker knows their whereabouts. It gives social workers a bad name. I was once a worker and I made sure siblings had contact with each other. And then someone was looking and wanting them, but yet children Services didn't make the connection. Star got emancipated real quick with no justification.
I have an adopted son, we rescued from the "system" at age 4, and his little half brother went to his biological father.. They never again got to see each other, and not for lack of trying on my part..they were physically, serially, and emotionally abused..the other child's father felt it was best to erase the past..as that one was less than two years old at that time.. Unfortunately, the poor child died at age 11..my son has never recovered from this.. The system sucks.. There were caseworker who truly cared, but they were few and far between.. I worked for social services for ten years..many there were lousy at their jobs, and only there for the paycheck and benefits of working for the government.