In “Is Veganism Safe for Children?,” a blogger named “thoughtfulness” writes:

A child has different nutritional needs than an adult. For instance, although we all need fat (see below), fat intake is especially critical to a child’s developing brain and nervous system.
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Vitamins A, D, B and K are essential to the human health and they need saturated fat for transportation and absorption. Vitamin A and D are especially linked to saturated fat since they are only available in food from farm animals. This is why I advocate to my clients to only drink whole milk, eat whole fat yogurt and other whole (not non- or low-fat) foods.

Twenty five percent of our body’s cholesterol is in the brain and that brain is made up of over 60% fat. We also need saturated (animal fat) to provide cholesterol. We need cholesterol to help sustain life, repair cell walls and to help manufacture nerve cells.

Please feed your children — and yourself and your loved ones — good-quality animal fats. We need the fats themselves, but we also need them to increase the assimilation of other nutrients.