My son is now 18 years old and he asked his stepfather to adopt him. My son doesn't currently have a relationship with his biological father. The child custody took place in the state of Texas. I need to know does my son need his biological father's permission even if he is an adult. We don't possess a lot of money since we are a blended family so can we file this without hiring an attorney? And if no, does anyone know how much something like this would cost?