Actor Matthew McConaughey took advantage of the Christmas holidays to propose to his long-time girlfriend, Brazilian model Camila Alves, the Hollywood heartthrob told his Internet followers. “Just asked Camila to marry me. Merry Christmas,” McConaughey, 42, said in a message posted on Twitter and WhoSay late Sunday. Alves, 28, and McConaughey started dating in 2006 and have two children: Levi, age three, and Vida, who turns two next month. The star of ‘Lincoln Lawyer’ and 2008’s ‘Tropic Thunder’ was proclaimed the ‘sexiest man alive’ by People magazine in 2005.