Who is Natalie Jastrow Henry from War and Remembrance and what is their importance?

Natalie is a Jew, married to Byron Henry and is the mother of Louis. She is traveling Europe with her uncle, Aaron Jastrow, a famous American writer, when the war breaks out. As Jews, they are suddenly without legal transportation and make numerous efforts to return to America. Natalie is strong and continues to be so after she, Aaron and Louis are detained several times for various reasons.