Rathna Lalani Jayakody, born on January 8, 1964, is the youngest in her family. Her father is an Ayurvedic doctor, and she attended Siddhartha Maha Vidyalaya and Kolonnawa Balika Vidyalaya. Rathna has two brothers and two sisters, including renowned actress Geetha Kanthi.

Rathna was married to actor Sampath Tennakoon, whom she met during the stage drama "Puthra Samagama." They have performed in over 50 stage productions together. Currently, she works as a teacher at Sri Rajasinghe Madya Maha Vidyalaya.