Frustrated with their diets
For the past three weeks I have been watching my nieces. I have them all day until mid-September. They're seven and five and have the worst eating habits I have ever seen. I don't know if it's just because my daughter is still so little and I'm just not accustomed to the diets of small children, but it seems completely wrong to me.
My SIL brings over gallons of premade Nestle chocolate milk, a bag of microwavable chicken nuggets, french fries, and Easy Mac every week. They eat nothing but that every single day. I have offered everything to them, but they will only eat that. They don't eat fruits, vegetables, fresh anything, and I have to force them to drink water throughout the day. I have made fresh fruit popsicles in hopes that they'd like them, but they refused to even try them. I put a side of carrots and ranch with their chicken nuggets one day they threw a fit that they were there. I've taken them out to eat and they act like infantile brats and refuse to get anything if chicken nuggets or macaroni isn't an option.
I don't know if I should begin insisting upon having them eat what I make, because honestly it's annoying to make lunch/dinner for me and my husband and then their disgusting crap food too. Should I say something to my SIL? I'm really just getting annoyed and grossed out.