Alright so i was watching some Mario theories because why not and there was a theory that Mario and Luigi have a 3rd brother which is Dr Mario and honestly, this makes sense, because if we think logically, it would be difficult to complete a vocational school in the field of Plumbing and 6-year studies in the field of Medicine at the same time. Also, Doctors are called by their surnames, and from the first SMB movie from 1993 we learn that Mario and Luigi's surname is... Mario! So Dr. Mario's name doesn't have to be "Mario". But then how did Dr. Mario get into his parents' house if he didn't appear in "Yoshi's Island"? Well, in my idealized version of the game, Baby Luigi does not appear because in my version he is their older brother who was not delivered by the Stork at the time. Instead of Luigi, Stork delivers Baby Mario and Baby Doctor Mario, and if you've played Yoshi's Island you probably know how the rest of the story goes. As for Dr.Luigi, and Dr.Peach... I don't think that Dr. Luigi needs to exist, and Dr.Peach can be easily replaced by a Original Character.

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