Title: Roll No 21
Content: Kris: Kris is a godly child mostly known as neele gobaare (blue balloon) by Golu. He is an incarnation of Lord Krishna. He has appeared in Mathura Anath Ashram to stop Kanishk and his evil plans. Kris stays as a normal student in the school but secretly changes into Krishna, the divine boy with mystical powers whenever it is needed. He shows childish traits such as playing, disliking studies and homework, and enjoying playtime with his friends. Like Lord Krishna, Kris also likes butter, ice cream. His skin color is blue (like Lord Krishna) in this series. He is voiced by Pooja Punjabi. Kanishk: Kanishk 
Title: Krrish (franchise)
Content:  The great-grandson of Sanjay and Sonia Mehra, grandson of Rohit and Nisha Mehra and son of Krishna Mehra and Priya Mehra in Krrish 3 .
Title: Krrish (franchise)
Content:  Dr. Siddhant has been holding him captive. Krishna follows Siddhant to his island lair, where a huge fight ensues between Krrish and the doctor's thugs. Krrish eventually defeats them and saves Priya and Rohit. In the final scene, Krrish mortally wounds Siddhant. Before he dies, Siddhant asks Krrish who he is, and Krishna reveals himself. After revealing to Rohit that he is his son, Krishna takes Priya and Rohit back to India, reuniting him with Sonia. Rohit finds out his wife, Nisha, died after he disappeared. He mourns her, together with his son and mother, but still thanks Jadoo (who is somewhere between the stars) for giving his family this gift.
Title: Krrish (franchise)
Content:  The protagonist of the series. He is the grandson of Sanjay and Sonia Mehra, the son of Nisha and Rohit, husband of Priya and father of Rohit "Ajay" Krishna Mehra. He inherited special abilities from his father, and was taken to a remote village as a child by his grandmother to hide his growing powers. He eventually becomes the superhero Krrish, using powers of super-intelligence and learning to quickly adopt new skills.
Title: Krrish (franchise)
Content:  Friend of Krishna, who eventually becomes his wife in Krrish and a journalist for Aaj Tak in Krrish 3. She is Sonia Mehra's granddaughter-in-law, Nisha Mehra's daughter-in-law, Krishna Mehra's wife and Rohit's mother (that she named after her father-in-law)
Title: Krrish (franchise)
Content:  of the second film, the characters Sonia, Rohit, Krishna, and Priya are the only members of the family that are still alive while Nisha died after a few days of Krishna's birth. The third film shows the entry of Kaal (Vivek Oberoi) who was created by Dr. Arya (Naseeruddin Shah) during an experiment on Rohit thus being Rohit's second son and the main antagonist of the film. Kaal apparently kills Krrish but he is saved by Rohit who dies while giving life to dead Krrish through his solar experiment. Krishna finally kills Kaal and by the end of the third film, Krishna, Priya and their son, Rohit (named after his grandfather Rohit Mehra) are alive while Sonia died somewhere between the events of Krrish and Krrish 3.
Title: Krrish (franchise)
Content:  A disabled boy who meets an alien that gives him special abilities. He is the main protagonist in Koi Mil Gaya. In Krrish 3, he becomes a professional scientist working in a government organization; he is the husband of Nisha, father of Krishna Mehra, father-in-law of Priya, grandfather of Rohit Krishna Mehra (named after him, nicknamed Ajay) and the son of Sanjay and Sonia Mehra.
Title: Krrish
Content: Hrithik Roshan as Krishna "Krrish" Mehra and Dr. Rohit Mehra, Krishna's Father (Double Role) ; Priyanka Chopra as Priya Kalyanan, Krishna's love interest ; Naseeruddin Shah as Dr. Siddhant Arya ; Sharat Saxena as Dr. Vikram Sinha ; Rekha as Sonia Mehra, Krishna's Grandmother and Rohit's Mother ; Manini Mishra as Honey Arora ; Archana Puran Singh as Nayantara, Priya and Honey's Boss ; Bin Xia as Kristian Li / Krrish ; Hemant Pandey as Bahadur ; Puneet Issar as Komal Singh ; Akash Khurana as Father, Krishna's Catholic School Principal ; Kiran Juneja as Amisha Kalyanan, Priya's Mother ; Yu Xuan as Kristian's Sister ; Preity Zinta as Nisha Mehra, Krishna's Mother (Special Appearance in flashback) ; Rakesh Roshan as Dr. Sanjay Mehra, Krishna's Grandfather and Rohit's Father (Archived footage from previous film) 
Title: Lakshmana (Krishna's wife)
Content:  The Bhagavata Purana states that she had ten sons: Praghosha, Gatravan, Simha, Bala, Prabala, Urdhvaga, Mahashakti, Saha, Oja and Aparajita. The Vishnu Purana says that she has many sons headed by Gatravan. The Bhagavata Purana records the wailing of Krishna's queens and their subsequent leap in Krishna's funeral pyre immolating themselves (see sati). The Mausala Parva of the Hindu epic Mahabharata which describes the death of Krishna and end of his race declares that only four committed, others kill themselves by burning themselves alive after being attacked by robbers.
Title: Krrish (franchise)
Content:  The film series covers the story of three generations of the Mehra family. It first begins with Dr. Sanjay Mehra (Rakesh Roshan) and his wife Sonia (Rekha) who are part of a car crash. Dr. Mehra has died while Sonia, who is pregnant, survives with injuries. This results in their son, Rohit Mehra (Hrithik Roshan), being born developmentally disabled. After receiving supernatural abilities from an alien he befriends, Rohit marries his best friend Nisha (Preity Zinta) by the end of the first film. Their son, Krishna Mehra (also Hrithik Roshan) is born with the same supernatural powers in the second film (Krrish) which he uses to help people, eventually turning into the superhero 'Krrish'. He is later romantically involved with city girl Priya (Priyanka Chopra). By the 

Question: what is the name of son of lord krishna?
Answer: Pradyumna.