No. The season 10 for American Idol is over as a television event and now the season begins as a concert tour. They both could make an appearance for season 11 of the American Idol when in begins in January 2012
If I am correct, there is an age limit of 15 to be on American Idol, at least that is what is was for the previous season (Season 10). Actually, the runner-up of Season 10(Lauren Alaina), was 15 when she auditioned and turned sixteen during the show.
The question in the related question will have current season 10 2011 American Idol information on who was voted off when Siobhan Magnus was the sixth contestant voted off American Idol 2010 on April 28 2010.