[3] She attended Miss Fines in Princeton and was separately tutored in art and music all the time making childhood trips to Europe.

Morris introduced her to the work of European modernists like Pablo Picasso, Fernand Léger, Georges Braque, and Juan Gris, which inspired her to explore a more abstract Cubist manner.

In 1943, Frelinghuysen's work was included in Peggy Guggenheim's show Exhibition by 31 Women at the Art of This Century gallery in New York.

[7] As Suzy Morris, the dramatic soprano appeared with the New York City Opera from 1947 to 1950, in Ariadne auf Naxos (in the title role, opposite Virginia MacWatters as Zerbinetta), Cavalleria rusticana (as Santuzza, conducted by Julius Rudel), Tosca (as Floria Tosca), Aïda (as Amneris, with Camilla Williams, Ramón Vinay, and Lawrence Winters, directed by Theodore Komisarjevsky), and Les contes d'Hoffmann (as Giulietta).

That performance, which was broadcast, also featured Jussi Björling, Marko Rothmüller, Martha Larrimore, the young Norman Treigle (as Samuele), as well as Audrey Schuh (as Oscar, her first major role).