In the foster care world the need for protect and prepare is so much greater and more difficult. Because foster children have been moved around, changed schools, most have not had adult role models and people that could protect and prepare them.
When they come to us they often feel, "It's too late. I don't need you or your protection or preparation." One of the most important piece of Choice Theory is "everything we get through the 5 senses is just information, what you choose to do with that information is what we all have to figure out."
Communicate with your foster children, help them evaluate their choices, and help them see where you are coming from and what you are trying to do.