How you made your grandmother glad

A Sunday school teacher was telling her pupils the importance of making others glad. "Now, children," said she, "has anyone of you ever made someone else glad?"
"Please, teacher," said a small boy, "I've made someone glad yesterday."
"Well done. Who was that?"
"My granny."
"Good boy. Now tell us how you made your grandmother glad."
"I went to see her yesterday, and stayed with her three hours. Then I said to her, 'Granny, I'm going home,' and she said, 'Well, I'm glad!'"