The two characters in this, a man and a girl, are both singing to a woman, or a parent. That parent seems to have somehow lost her child in a way that she may have been guilty of, so it's not too easy for people to comfort her. She may have lost custody of them in some way. There's also the possibility that the person they are talking about couldn't have kids.
As you can see, the black tin box makes the male speaker uncomfortable because only people who don't have children have them. Same goes for the woman who notices the youth playing outside while she is writing the postcard.
The two characters in this, a man and a girl, are both singing to a woman, or a parent. That parent seems to have somehow lost her child in a way that she may have been guilty of, so it's not too easy for people to comfort her. She may have lost custody of them in some way. There's also the possibility that the person they are talking about couldn't have kids.
As you can see, the black tin box makes the male speaker uncomfortable because only people who don't have children have them. Same goes for the woman who notices the youth playing outside while she is writing the postcard.