Kannadi Pookal is a honest remake of the Malayalam movie Ente Veedu Appuvinteyum. The movie is all about seven-year-old Vasu (Master Ashwin) who spends his days happily with his father Sakthivel (Parthiban) and step mother Meera (Kalyani). Both pour boundless love on him.
As it happens, she gives birth to a baby boy and they show the same love and affection towards the new kid. Unable to tolerate the 'competition' for parental love,Vasu kills the child spraying a disinfectant.
The whole family breaks down and sinks in an emotional quagmire. Eventually, Vasu's wrongdoing comes to light and is sent to a reformatory school by the police. Though his parents are initially shocked by his act, they eventually come to terms with reality and plead for their son to be sent home.
Meanwhile, a psychiatrist Sarath Babu steps in and provides counseling to the boy. After spending some years in the reformatory school, Vasu returns home one- ay to see their parents with a new kid. The rest is whether he accepts the young kid or not?