For the uninitiated, Laal Singh Chaddha was the Bollywood debut of Nagarjuna’s son Naga Chaitanya that starred Aamir Khan and was the official adaptation of Forrest Gump. In a family of four actors, there are a lot of “bittersweet moments” every year, says veteran star Nagarjuna, who is basking in the success of “ Brahmastra: Part One Shiva ” that …