Junius II had a younger sister, Caroline Lucy Morgan (1873–1942),[3] a philanthropist,[4] who never married.

[3] Morgan was a generous benefactor of the Metropolitan Museum of Art in New York and gave many works to the (future) Department of Drawings and Prints from a broad range, dating mainly from the sixteenth century, including 2 woodblocks and many prints by Albrecht Dürer in 1919.

He was equally generous in his gifts to what is now the Princeton University Art Museum, many of whose strengths in collecting prints and drawings can be traced to Morgan.

[6] In January 1932, he was awarded the Order of the Crown of Italy by Signor Comandante Emanuele Grazzi, the Italian Consul General.

[3][15] His funeral was held at the American Cathedral Church of the Trinity in Paris,[16] and he was buried in Cedar Hill Cemetery.