If the child
In other words, if he sucks a breast of minutes, he will receive almost as much milk, how many and in minutes.
If you allow the child to suck a breast so much, how many he wants, you with surprise are convinced that once he will suck only minutes, and another minutes.
This example proves surprising adaptability of a mammary gland to needs of the child.
If the child sucks only one breast in each feeding and does not want any more, you will not force it to suck more.
But the child who sucks both mammary glands in each feeding and nevertheless sucks a finger, represents other problem..