It is likely that this rumor originated from a combination of factors:
* Hollywood Gossip: Hollywood was (and still is) a breeding ground for rumors and speculation.
* Marilyn's Public Image: Marilyn was a sex symbol and a figure of fascination, so any unusual physical traits could have been exaggerated or fabricated for sensationalism.
* Physical Imperfections: People are often fascinated by physical differences, and it's possible that someone saw something about Marilyn's feet that they misinterpreted.
However, there is no credible source to support the claim that she had six toes.