How does tom make 3 unpleasent things into pleasent things

The boys have gone to Jackson Island and their raft has disappeared~ a not so pleasant loss is a relief. They boys go fishing.

Everyone believes the boys are dead after finding their raft down the river. The funeral is an unpleasant occassion made much less unpleasant by their reappearance.

Tom is chastised by Aunt Polly because she found out that he had come back to the island and spied on the family while they'd believed him dead~ he makes it pleasant by telling her he wanted to leave a message but didn't want to spoil the surprise he'd planned. She didn't believe him until she found the note in his pocket. The message brought on tears and a pleasant experience.