Donnie has always wished for a child to care for so when you end up in his care he can’t help but want to keep you his cute, innocent, helpless child for the rest of your life. He wants you dependent on him and only him. What use do you have for anyone else, he’s your father and the only family you’ll ever need. You will stay nice and safe tucked away from the world where he can keep you under his care for the rest of your life. So he’ll keep you hidden from the world, all for himself.