The 19-year-old upcoming Playgirl model went on CBS's The Early Show yesterday and hinted that he knows secrets about Palin that could get her "in trouble and could hurt her." He claimed that she referred to her infant son Trig, who has Down syndrome, as "retarded." But he would not elaborate on any of the other possibly incriminating information he claimed to know. "I'm not gonna go that far," he said. This prompted a sharp rebuttal from the former Alaska governor. She called Johnston's comments "mean spirited, malicious and untrue." "Trig is our 'blessed little angel' who knows it and is lovingly called that every day of his life," Palin said in a statement. She also questioned the credibility of someone who would pose by Playgirl. "Consider the source of the most recent attention-getting lies," she says. "Those who would sell their body for money reflect a desperate need for attention and are likely to say and do anything for even more attention."