Very interesting observation.

• Polly Ann Young (eldest sister) as Grace Hubbard
• Sally Blane (second sister) as Gertrude Hubbard
• Loretta Young as Mrs. Mabel Hubbard Bell
• Georgiana Young (younger half-sister) as Berta Hubbard, and
• Spring Byington as their collective mother, Mrs. Hubbard

Polly Ann married Carter Hermann; Sally married actor Norman Foster (Claudette Colbert's ex); Loretta married Grant Withers, Tom Lewis and Jean Louis; Georgiana married actor Ricardo Montalbán.

Such a wonderful all-star lineup, "The Story of Alexander Graham Bell" (1939) entire cast, indeed....

• Don Ameche as Alexander Graham Bell
• Henry Fonda as Thomas Watson
• Charles Coburn as Gardner Hubbard
• Gene Lockhart as Thomas Sanders
• Bobs Watson as George Sanders
• Russell Hicks as Mr. Barrows
• Paul Stanton as Chauncey Smith
• Beryl Mercer as Queen Victoria
• Charles Trowbridge as George Pollard
• Jonathan Hale as President of Western Union (Mister Dithers)
• Harry Davenport as Judge Rider (GWTW Dr. Meade), and
• Elizabeth Patterson as Mrs. MacGregor (Little Ricky's Babysitter).