Premise: Effie Crockett (1857 - January 7, 1940), also known as Effie I. Canning, also known as Effie C. Carlton, was an American actress. She is credited with having written and composed the lullaby "Rock-a-bye Baby"; by some accounts she created the song in 1872 while babysitting. Because of "Rock-a-bye Baby", she is credited in over 100 films, many made decades after her death.
Hypothesis: Effie Crockett lived to be no more than five decades old.