How does Ravi get milk for the kitten?

Ravi managed to get the milk for the kitten by cleverly fooling his mother. He told his mother that he is feeling hungry. Therefore, he wants some milk to drink. When his mother gives him milk instead, of drinking it he keeps the milk for the little kitten. As his mother asks to give the tumbler back after drinking the milk he escapes the situation by saying that he will keep the tumbler back after washing it.