Her name is Monica LeRoi. The name of the LP is "La Musique de Jim Olivier." The LP is on the Swallow Label and was released in 1985. That may or may not provide some hints on where to look further, but maybe it will help a little bit.
thanks to both of you. I have ordered the essential collection with both songs on it. Evidently she sings with her brothers on their record but she must not have started singing by herself(what a shame)