Hi Debx and welcome to the forum!
Prior to diagnosis the body starts to breaks down fat and muscle as it cannot utilise the food we consume due to lack of insulin, this is why sudden weight loss and extreme thirst is the first sign of diabetes, once we get started on insulin the body wants to build up its reserves again and this is why we are starving hungry post-diagnosis.
So hopefully once they get her insulin doses right and you get the hang of carb counting there's less of a chance of her being hungry between meals, in the mean-time for snacks between meals try to get her to eat foods that are low in carbs such as cheese, ham slices or carrot/celery sticks with a dip. The suggestion by MrsDMiles to join other Mum's on Facebook is an excellent idea!