Who is Charlotte Singer from The History of Love and what is their importance?

Charlotte Singer is the widowed mother of Alma and Bird Singer. Her husband, David, died of cancer approximately eight years prior to the novel's setting. She is from England and is small and fair-skinned. After David's death, she struggles to overcome her grief and be a good parent to her children. Skilled in foreign languages, Charlotte works as a translator of books. When she receives a request from Jacob Marcus to translate The History of Love for $100,000, Charlotte takes the assignment, not only to support her family, but also in honor of her late husband, as the book was a significant part of her relationship with David.