Hooray for the colon in jno's example, which is how The Times , as well as The Guardian,introduces direct quotes: Her mother said:"Let's have tea", and boiled the kettle. (Colons are endangered, but not as much as semi-colons are, and must be protected ) . Put a comma in, if only to indicate a pause in speaking, after the quotation marks. The comma goes inside when the sentence reads: "Let's have tea," said her mother.
Can't think it really matters very much, but that thinking put the colon in peril!