MUMBAI: Telugu star Allu Arjun penned an emotional note on his son Ayaan's birthday on Friday, with a cute picture of the little boy with his birthday cake.

Arjun took to Twitter to share the picture and his note.

"I used to think 'what is Love ?' all my life. Many times in the past I felt strong feelings but I was not sure if it was love. But after you came into my life I now know what LOVE is. You are the LOVE. I Love you Ayaan. Happy Birthday My Baby," the actor wrote.

Arjun married Sneha Reddy in Hyderabad in March 2011. The couple has two children, son Ayaan and daughter Arha.

On the work front, Arjun's latest release "Ala Vaikunthapurramuloo" opened in January and went on to become a huge hit. The film co-stars Tabu and Pooja Hegde.

The actor will next be seen in "AA20" directed by Sukumar. The film also stars Rashmika Mandanna, Vijay Sethupathi, Prakash Raj and Jagapati Babu.