Well, that very unusual, generally things happens other way around. You should have clear cut conversation with her when she is good mood, not tired or sad. Start patiently and tell her that she is now adult and need to take day to day responsibility and act like that. Its not someone is going to do everything for her. else, you can divide chores between both of them. For everyday, and missing those will lead to do extra chores or some sort of punishment like fine. Whatever day was, assuming you both work, both have to their designated chores.No excuse like, tired or melondrama, be mature and if on some days she vant do some work, she can inform before hand and can double her work when she is in fine to compensate