Her professional career started with Gert Balke as the duo April Shower, who had a minor hit with "Railroad Song" in 1971.

Her father ran a restaurant in Amsterdam, where she met singer Ramses Shaffy, with whom she started touring.

[2] In 1977, Lester's song "De mallemolen" ("The Merry-Go-Round"), with music written by her brother Frank, was chosen by a celebrity panel as the winner in the Dutch Eurovision selection.

Although "De mallemolen" had been considered a strong contender prior to the contest, it could only manage a disappointing 12th-place finish of 18 entries.

[4] After her Eurovision appearance, Lester worked in a variety of both musical and dramatic stage roles, including works by Lorca (Blood wedding), Euripides (The Trojan Women) and Joshua Sobol (Ghetto).