BY STEVE ROTHAUS, srothaus@MiamiHerald.com
''She's not just doing this because she wants to perform on a cruise ship,'' O'Donnell publicist Victoria Varela said Thursday from New York.
Estefan's publicist confirms that the singing star's going to perform aboard O'Donnell's weeklong gay-oriented R Family Caribbean cruise, which departs from the Port of Miami on Feb. 18.
''She's going to do something. Rosie is one of her closest friends,'' said David Naranjo, media director for Estefan Enterprises in Miami Beach. ``Exactly what, we just don't know.''
Estefan is riding high these days: Her second children's book, Noelle's Treasure Tale, is No. 3 on The New York Times children's bestseller list.