The Kalin Twins, born Harold "Hal" and Herbert "Herbie" Kalin on February 16, 1934, in Port Jervis, New York, are an American pop singing, songwriting, and recording duo. After moving to Washington D.C., they started performing together, pooling their funds for a demonstration record in November 1957. In 1958, they achieved significant success with the release of debut single "When". The song reached number 5 on the American charts and topped the UK Singles Chart on September 13, 1958. It sold over two million copies and remained in the UK listings for eighteen weeks. The Kalin Twins had a second hit later that year with "Forget Me Not" which peaked at Number 12 in the US Billboard chart. After releasing several more singles under Decca Records, including "It's Only The Beginning" (1959) and "When I Look In The Mirror", (1959) they saw their popularity decline despite continuing to perform as headline nightclub acts into the 1960s. Post-1959, none of their releases reached the charts again. After returning to college and pursuing day jobs in the late 1970s and early 1980s, they resumed performing at a mutual friend's invitation and later supported Cliff Richard at his Wembley Stadium concerts in 1989. Harold Kalin died on August 24, 2005, while Herbert Kalin passed away from a heart attack on July 21, 2006.