@Fiddle Depends on how much time she spends with you. It’s an uphill battle if she’s not living with you and she isn’t the only one in the house eating the right way.
You can fix a fat girl, but it’s less a concerted effort to address issues, and more a case where she just follows the same eating patterns you have, takes on your habits, and stops gorging herself because it’s awkward to do so when you aren’t doing so.
Lots of variables. But I wouldn’t be putting her through anything you aren’t doing yourself. Also lots of praise & rewards, always heps in training uh….people