The report looks pretty good after a quick look through it. Lots of good sensible advise about breast feeding, activity and sleep. Limiting TV marketing exposure and sugary drinks. Parts of the healthy eating section seem the weakest bit as they mostly just repeat standard USDA recommendations.
"offering an age-appropriate volume of breast milk" - I found that bit amusing.
I'm not sure how your brother in law read all that and reached the conclusion "they are eating too much fat!". The recommendations don't even mention dietary fat.
Has your brother in law seen your blog?
If all school children ate as well as yours appear too at lunchtime I doubt there would be any childhood obesity. I'm sure very few children get so many fruits and vegetables or such a variety in their lunchbox. Few of the meals you have posted on your blog seem all that high in fat either.
There is just too much focus on macronutrients like "fat" instead of eating whole foods and less processed foods. Kids don't really need high or low fat, high or low carbs, they just need a variety of wholesome food or all kinds.