lookong for advice.. I have noticed that my oldest daughter does not get the healthiest snacks(food)…

lookong for advice.. I have noticed that my oldest daughter does not get the healthiest snacks(food) at my parent's house. She is kinda the homebody & she's not the most athletic. My father constantly spoils her with McDonald's and doughnuts, even after I had asked him to stop. Yet, he still does it and I do not know how to politely ask him to stop without sounding like the asshole here!