John and Patsy Ramsey filed a $25 million lawsuit against the Star supermarket tabloid on Tuesday, alleging the publication libeled their 12-year-old son, Burke, with stories that named him as the prime suspect in the killing of his sister, JonBenet. The federal lawsuit said the stories, published May 25 and June 1 (but later retracted), were false and defamatory, and subjected the boy to “public hatred, contempt and ridicule.” One story ran with a front-page photo of the two children under the headline “JonBenet Was Killed by Brother Burke.” The Star said it would vigorously fight the suit and would, in its pages, “conduct a complete investigation of the murder, pursuing avenues of inquiry that were not available to state investigators.”