Carly Simon is upset after her sisters passed just one day apart.

The 78-year-old singer is in mourning after Broadway composer Lucy Simon died of breast cancer just one day after former opera singer Joanna Simon died of thyroid cancer.

Lucy was 82 years old, while Joanna was 85.

Carly, Lucy, and Joanna were born in New York to parents Richard L. Simon, founder of the Simon Schuster publishing company.

Their mother Andrea was a civil rights activist and singer.

Lucy and Carly formed their own singing duo, the Simon sisters, in the early 1960s.

 While they both pursued solo careers, Lucy found success as a composer.

Joanna made her New York City Opera debut as Mozart's Cherubino in 1962.

Lucy and Joanna's brother, photographer Peter Simon, died of cardiac arrest in 2018 at the age of 71 after being treated for cancer.