Chennai: Superstar Mahesh Babu said his son Gautam, who turned 11 on Thursday, is the reason for his existence and his happiness.

"He is the reason for my existence. My driving force. My son. My world. My Happiness. Happy birthday, Gautam. Stay blessed," Mahesh tweeted on Thursday.

Mahesh is currently shooting for his upcoming Tamil-Telugu bilingual "Spyder" in Romania.

The film is being directed by A.R. Murugadoss. Mahesh plays an Intelligence Bureau officer in it.

Also starring Rakul Preet Singh, the makers are currently filming a duet on the lead pair in Romania.

Produced by Tagore Madhu, the film is slated for release on September 27.

"Spyder" also stars SJ Suryah, Bharath, RJ Balaji and Priyadarshi Pullikonda among others.