Complex sentence: The film's USP is the appearance of three generations of the famous Kapoor family starring Prithviraj Kapoor, his son Raj Kapoor, Raj Kapoor's son Randhir Kapoor (in his acting debut) and Randhir's real-life wife-to-be Babita.
Split into simpler sentences: The film's USP is the appearance of three generations of the famous Kapoor family. It stars Prithviraj Kapoor, his son Raj Kapoor, Raj Kapoor's son Randhir Kapoor (in his acting debut) and Randhir's real-life wife-to-be Babita.