The single most helpful phrase for this parent of young adult children: “Wow, that’s (exciting / unnerving / scary / fantastic!) What do you think you’re going to do?”
Transitioning from being the kids’ Life Skills Instructor (“Wash your hands!” “Do not put the cat in the dishwasher!” “Do not put your brother in the dishwasher!“) to becoming their sounding board as they navigate their own lives, is quite an adjustment.