After the release of Dolly Ki Doli, Sonam Kapoor has been working so hard shooting for her next film ‘Prem Ratan Dhan Payo’ that the work took toll voer her and the actress fell ill. She was hospitalised about three days ago after suffering from respiratory infection on the sets of 'Prem Ratan Dhan Payo' at ND Studio in Karjat.