I'm not aware of any connection between Harlow and Temple, Letty. The Bluebird in 1940 was Shirley's first box office flop. For three years prior to that movie, Shirley was box office champion.
Some celebrity birthdays for December 11:
December 11
1803 Hector Berlioz, composer (La Côte-Saint-André, France; died 1869)
1843 Robert Koch, physician/bacteriologist (Clausthal, Germany; died 1910)
1882 Fiorello La Guardia, New York City mayor (New York, NY; died 1947)
1913 Carlo Ponti, film producer (Milan, Italy)
1918 Aleksandr Solzhenitsyn, novelist (Kislovodsk, Russia)
1931 Rita Moreno, singer/actress (Humacao, Puerto Rico)
1940 Tom Hayden, politician/activist (Royal Oak, MI)
1942 Donna Mills, actress (Chicago, IL)
1944 Brenda Lee, singer (Atlanta, GA)
1945 Teri Garr, actress (Lakewood, OH)
1954 Jermaine Jackson, singer/musician (Gary, IN)
(Rita Moreno in West Side Story for which she won an Oscar)