A Cub Scout troop was thirty minutes late to the den meeting. 

The den mother asked them severely, “Why are you so late?”

“Oh,” said one boy, “we were helping a little old lady cross the street.”

“That’s a nice thing for scouts to do,” said the mother. She paused. “But it shouldn’t make you a half an hour late.”

“Well, you see,” said another boy, “she didn’t want to go.”