She needs more protein (up to 2g per lb) and less carbs plus 30-50g fat per day.
At the moment she has reached a plateau and is still at low pro/medcarb/lowfat/ Changing to high pro/lowcarb/medfat will make the difference as will changing her split to 4 or 5 days lifting and 3 days cardio.
Make sure she is lifting heavy and is still using compound exercises as the basis to her workouts. Here is an example of what her leg day should look like:
12,10,8,6 - free barbell squat
12,10,8,6 - hack squat
12,10,8 - leg press
12,10,8 - leg extension
12,10,8,6 - standing calf press
I always do hams with back.
This will ensure she is increasing muscle/firmness/metabolism and losing fat as long as she eats clean.
Any more cardio will mean loss of muscle/firmness/metabolic rate.So she needs to train heavy, ignore abosolute weight and concentrate on bf% - as it lowers you get thinner.