Celebrity watchers were stunned last week when Britney Spears‘ clean-cut 16-year-old sister, Jamie Lynn, suddenly announced in OK! magazine that she is pregnant — so stunned that OK! had to head back to the printer and is approaching sales of nearly 2 million copies of the issue containing the exclusive interview with Jamie Lynn and her mom, Lynne Spears. After Britney’s tragic decline and sometimes bizarre behavior, Jamie Lynn seemed set to succeed her sister as America’s sweetheart. Now friends fear she could be on the same slippery slope. In the OK! magazine interview she describes herself as "shocked and scared" but reveals she will hang on to her baby and that her boyfriend, Casey Aldridge, and her mom will be standing by her. "I’m the one who has to live with it for the rest of my life," she says. "I put myself in this position, an adult position, so I have to act like an adult and take responsibility for what I did." For the complete interview with Jamie Lynn and her mother, pick up the new issue of OK! — still available on newsstands everywhere!