In 1966, Lai, her sister and other four males singers formed a musical band BumbleBee to promote their traffic and road safety song in Hong Kong. In 1967, Lai joined RTV to attend its first Artist Academy. One of her classmates was Liza Wang.
In 1967, Lai took a stage name Sum Sum (森森), while her sister's stage name went first as Bun Bun (彬彬) but soon changed to Ban Ban (斑斑). In the late 1967, Lai contested and won the Hong Kong's Queen of Singing Diva (香港歌后) title, and was encouraged by Robert Chua to sign up to become one of TVB's first batch of actors and actresses. She also became a host in the TVB's variety show Enjoy Yourself Tonight (歡樂今宵).[1]
Sum Sum took up a training lesson of Jeet Kune Do with Bruce Lee while he was in Hong Kong with his young son Brandon on 3 April 1970, prior to Lee's appearance in Enjoy Yourself Tonight four days later in 7 April.[2]
In 1972, Sum Sum formed a musical duo group Sum Sum Ban Ban (森森斑斑) with her sister. Ban Ban also joined in to host Enjoy Yourself Tonight with her sister in 1973.
In 1979, they released their first album Star, Moon, Sun (星星.月亮.冇太陽). Sum Sum and Ban Ban left TVB in 1983 to join ATV to further pursuit their acting and singing career.
In 1997, she was invited by TVB to host in the reestablished but short-lived variety show Enjoy Yourself Tonight. She also made live advertising roles for HKTV on a weekly basis.
From 1999 onwards, Sum Sum, with her sister Ban Ban, would host and perform for several entertainment companies in many international venues and charity events, i.e. United States, Canada, Singapore, Macau. During that period on 27 September 2003, she was noted to be the first Chinese singer to perform with the Mississauga Symphony Orchestra at the Mississauga Convention Centre in Mississauga, Canada.
Her last acting appearance was in 2006. In May 2012, she was interviewed in the ATV's television show aTV 100 Celebrities
Personal life
In December 1977, Sum Sum married Robert Lee (李振輝), brother of Bruce Lee. They had a son named Clarence Lee Ka Ho (李嘉豪) in 1980, and they divorced in 1983. Sum Sum retained custody of their son. Clarence's stage name is "家豪".
She later was remarried to Macao businessman Wong Chung-tak (王宗德), ceremony was held at a hotel in Vancouver in 1992 as prepared by her friend Louise Lee, and moved to Macao.[3]