You have as much to do as she does. Make sure that she eats healthy, plenty of fruit instead of snacks, no sodas - water, lots of vegetables, limited deserts, NO fast foods and make sure she has the opportunity to get plenty of exercise, It's never too late to develop good lifestyle changes.
its not eat less its eat more not more junk food but helthy food take 1 of her fav fruits or veggies and turn it into a snack and go walk whenever you can eat eggs for breakfeast and do alot of excercises
Being the mother you must lead by example. NO fast foods, NO chips,cookies cakes ect.Do active things WITH her. Keep fresh fruit and veggies ready to eat. Sit at the TABLE for all meals and snacks together. Talk while you eat. Have conversations. Let her help with mealtime. Cook Together.