Mumbai, Dec 25 : Bollywood superstar Salman Khan is turning 56 on Monday and he had a pre-birthday celebration on the sets of 'Bigg Boss 15' with the team of the upcoming pan-India epic 'RRR'. In the upcoming episode, Salman will be celebrating his birthday in advance. Actors Alia Bhatt, Jr NTR, Ram Charan and director S.S. Rajamouli visited the sets to promote their upcoming film 'RRR'. Alia took this opportunity to wish Salman in her own style. She opened the episode herself by greeting the viewers and welcomed host Salman by singing a birthday song for him with a live band. To amp up the celebrations and entertainment, Salman invited filmmaker Rajamouli, actors Jr NTR and Ramcharan on the stage to join Alia. To make Salman's day even more special, Alia informs him that the contestants have a surprise for him in store. As all of them virtually meet the contestants through 'MeTV', the housemates give a power-packed performance on Salman's super hit songs which brought a big smile to his face. Salman too was seen grooving along with the housemates and even performed his hook steps. Concluding the celebrations on a sweet note, Rajamouli got a cake for Salman, calling it a small gift from the cast. Overwhelmed by the gestures, Salman thanks the 'RRR' cast and cuts the cake with them as well as the housemates. /IANS