Sonakshi Sinha had a working birthday this past weekend. Even as her latest film, Rowdy Rathore, opened to a thumping response, Sonakshi was focussed on shooting Son Of Sardaar with Ajay Devgn in Mumbai on June 2, when she turned 25. Ajay, though, ensured Sonakshi's birthday wasn't about all work and no cake. Along with his buddy and the film's director Ashwini Dhir, Ajay arranged for a quick cake-cutting ceremony for the actress.