And what happens when its your kid who finishes the milk and doesn't mention it to you?
Or you didn't finish the milk, but didn't realize it had gone bad until after you got home with ingredients for a meal depending on milk.
Well, then, of your cows can only be milked on the 'morn you'll have to do with milking one of the goats.
Have a shared shopping list with the family. Teach your kid to put the milk on the list after they finish it. Be at least somewhat aware of how old your food is. Problem solved. Somehow we managed this model for a century.