Amara was born on 22 August 1939 in Batuwatta, Gampaha as the fifth child of the family with eleven siblings. Her father, Don Wiyolis Kasthuriarachchi was the Head Master of the Hanwella Primary School. Her mother, Dona Alpinona Meegahapola was a housewife. Her father was from Batuwatta and my mother was from Mathugama. She was educated at Hanwella Primary School and later attended to Hanwella Rajasinghe Central College. She played netball and attended other activities at school including learning ballet under maestro Wasantha Kumara.
She was married to Dr. Dayarathna Ranatunga (born as Ranatunga Arachchige Dayarathna Ranatunga) where they got registered on 8 August 1963 and celebrated wedding on 30 January 1964. Dayarathna was born on 29 October 1940 as the youngest child to a family of six in Nawala, Nugegoda. His father Charles Peter Ranatunga was a school principal and his mother Dona Maslin Kolombage was a housewife. He completed education from Ananda Sastralaya, Kotte. After SSC exam, he attended to Zahira College, Colombo and studied in the Maths stream. In 1964, he was selected to a research officer post at the Tyre Corporation. Without any satisfaction from the career, he again moved to music where he was invited for Sri Lanka Broadcasting Corporation (SLBC). In 1969, Dayarathna joined with SLBC as the first Producer in the Music Unit where he was promoted as the Head of Department - Controller of Sinhala Music in 1978. Dayarathna's elder sister, Somalatha Ranatunga is also a singer. Dayarathna's maternal uncle D. M. Kolambage was the first Sinhala announcer at the Radio Ceylon.
The couple has two sons: Nanditha Sarada, Pulasthi Indika and a daughter, Kumudumathie Rupashika. Their son, Pulasthi sang the song Senpathiyan Gena Nawpathiyan Gena with mother Amara at the age of eight. Nanditha is married to Sadhana Abeysekara, who is the granddaughter of late songstress Wasantha Sandanayake. Sadhana's sister, Supriya is also a popular singer in Sri Lanka.
On 16 October 2018, Amara died at the age of 79 while receiving treatment at a private hospital for a heart attack. Her remains were brought to the University of the Visual & Performing Arts at 1.00 pm and later the final rites were held at the Borella General Cemetery on 18 October 2018.
