Vivek Oberoi overjoyed at birth of nephew

'My sister Meghna just gave birth to a beautiful healthy baby boy! I'm officially a maama now! u00a0Thank you for all the prayers and blessings,' Oberoi tweeted. 'One of the happiest moments of my life! Holding my nephew for the first time! Felt so special,' he further posted. Meghna married businessman Amit Bama in 2008.