Prime Minister Manmohan Singh faced some embarrassing moments at a function to mark the anniversary of the December 13 Parliament attack of 2001. A tearful Vimla Devi, wife of ASI Nanak Chand, who was killed in the 2001 terrorist attack, turned up at a function that was also attended by Leader of the Opposition L K Advani and Home Minister Shivraj Patil to pay tributes to the martyrs.