Both are to be found in milk, one in the cream and the other in the skim milk or whey.

For this reason children should have whole milk rather than skim milk.

Of course, butter and skim milk should produce the same result as whole milk.

Eggs also have these requisites and can be used to supplement milk for either one, but as a rule it is more practical to depend upon milk, and usually more economical.
For little children, milk is best served as a beverage.

But as children grow up, the fluidity of milk makes them feel as if it were not food enough and it is generally better to use it freely in the kitchen first, and then, if there is any surplus, put it on the table as a beverage or serve it thus to those who need an extra supply--the half-grown boys, for instance, who need more food in a day than even a hard-working farmer.
A good plan is to set aside definitely, as a day's supply, a quart apiece for each person under sixteen and a pint apiece for each one over this age.