Why would 24x7 contact with the mother and no one else be "the best care" for the kid? Who says it's not a part time job for two people? Who says our ability

Why would 24x7 contact with the mother and no one else be "the best care" for the kid? Who says it's not a part time job for two people? Who says our ability to cooperate in groups, the key to our success in practically every area, would skip this one?