The two older Bunker children did not know where to look for their little brother. But Russ had an idea. He usually did have pretty bright ideas, and Rose admitted this fact. "You know we got up early this morning," Russ said to his sister, "and we have been awful busy. And here it is noontime. Mun Bun doesn't usually have a nap until after lunch, but I guess he's gone somewhere and hidden away and gone to sleep. And when Mun Bun's asleep it is awful hard to wake him. You know that, Rose Bunker." "Yes, I know it," admitted Rose. "But where could he have gone?" Russ thought over that question pretty hard. Daddy Bunker would have said that the little lost boy's older brother was trying to put himself in Mun Bun's place and thinking Mun Bun's thoughts. Now, if Mun Bun had been very sleepy and had crept away to take a nap, as he often did after lunch when they were at home, without saying anything to Mother Bunker about it, where would he have gone to take that nap on this steamboat? Mun Bun was a bold little boy. He was seldom afraid of anything or anybody. Had he not instantly made friends with Sam, the strange colored boy, at Aunt Jo's house? So Russ knew he would not be afraid to run right out on the deck among the other passengers. "But that would not be a nice place to go for a nap," said Russ aloud. "What wouldn't?" asked Rose, quite surprised by her brother's sudden speech. "Out here on the deck. No, he didn't come out here at all," said Russ, with confidence. Russ was an ingenious boy, as we have seen. Once having got the right idea in his head he proceeded to think it out. "Come on back, Rose," he said suddenly, seizing his sister's hand. "What for?" "To find Mun Bun." "But he isn't with Mother!" "I bet--No, I don't mean that word," said Russ. "I mean I _think_ he is with Mother, only she doesn't know it." "Why, Russ Bunker, that sounds awfully silly!" But she followed after him in much haste. They came running to the two staterooms which Daddy Bunker had engaged. Mother and the other children were the center of a group of sympathetic people in the corridor. "Oh! did you find him?" Rose cried. "Of course not," said Vi. "Where should we find him?" "Here," announced Russ, pushing through the crowd. "Of course he isn't here, Russ," said Vi. "Can't you count us? Mun Bun is not here." "Well, let me see," said the boy, and he pushed into the bigger stateroom where his mother had been working when Mun Bun disappeared. Then he opened the door between that room and the other room. It was all quiet in there. He glanced into the two berths. There was nobody in either of them. "You are mistaken, Russ," whispered Rose, looking in at the door he had left open. "He can't be here. Daddy has just come and says the captain has promised to have the ship searched." But without making any reply Russ Bunker went down on his knees, looked under the lower berth, and then stretched an arm under and grabbed something with his hand.