When my kids turned 18 they were asked by their care providers to complete new forms to authorize who could receive information about their care. Even though they live at home and are in our insurance plan, we cannot receive any information about their care without their permission, although we will see the name of the treatment provider when we are billed for services.

Interestingly, this type of permission is also required before we are allowed to obtain any information about our children's high school and college grades, etc. once they turn 18. The university does, however, thoughtfully allow us to be "authorized payors" on the student accounts.