Mortimor (Cary Grant): "Elaine. Elaine, darling, I love you so much. I can't go through with our marriage.
Elaine (Priscilla Lane): "Have you suddenly gone crazy?"
Mortimor (Cary Grant): "No, No; I don't think so but it's only a matter of time. Now, look darling. You wouldn't want to have children with three heads would you? You wouldn't want to set up housekeeping in a padded cell? No, that would be bad.....Look, I probably should have told you this before but you see, insanity runs in my family. It practically gallops!...."
Arsenic and Old Lace (1944) Directed by Frank Capra