It is on account of the grown-ups and their ways. When you tell them that you have made a new friend, they never ask you any questions about essential matters. They never say to you, "What does his voice sound like? What games does he love best? Does he collect butterflies?" Instead, they demand: "How old is he? How many brothers has he? How much does he weigh? How much money does his father make?" Only from these figures do they think they have learned anything about him.
To forget a friend is sad.
Not every one has had a friend.
And if I forget him, I may become like the grown-ups who are no longer interested in anything but figures...
The grown-ups are very strange.