Baby Luigi Joestar

Baby Luigi Joestar (ベビールイージジョースター Beibī Ruīji Jōsutā) is a member of the Joestar family, who is referenced in the Epic Crossover arc of Part 5. Gunner states that he will attempt to RP as him, though he fails. Baby Luigi Joestar derives from the totally real and not fake Jojo X Mario crossover. His stand is "Baby" named after the Justin Beiber song. The ability he gains transforms him into a fire adult Luigi for a short period of time.

Rumors
Rumors have circulated that a possible spin-off series focused on the character could be in development. Inside sources say that the only issue is making the series appropriate for young Mario fans, as well as tell the story of a tragic deity in a baby's body.

Rumors have also stated that a script for a manga exists, but was cancelled. This could be due to Gunner, the leading man behind the project, deciding to leave the project to work on the controversial scene in the Part 5 anime in which Clay and Gunner make Hello Boyos jokes for an entire five minutes.

 UPDATE:  Gunner confirmed in an interview with ifuckninjaturtles.uk that a series was in development at one point. He has stated that there is not one main reason for cancellation. Many reasons had factored in. These factors had included


 * Gunner's hiatus at the time
 * The Film Bro saga's development
 * The Night at It's a Small World being put as #1 priority
 * Nintendo gave Gunner Brie Larson's finger in the mail as a threat if he continued further

The rumored scripts are real, though there are no intentions to release them. With Nintendo's threats and fear that the scripts will make people further clamor for the long rumored series, no release was/is planned for these lost scripts.

Gunner has also confirmed that the series was also in development, though the delays and development issues all round out to the same reasons of the manga, as they were developed simultaneously.

Theories
A popular theory surrounding this topic is that he was the man who stole the lightsaber in The Film Bro. Though Gunner has stated that The Film Bro 3 would debunk the theory. Leaked DMs of Gunner asking The Costume Kid to make a Luigi costume have surfaced, making some expect that the collab with the two with BLJ involved was coming in the form of the third Film Bro, which has been confirmed to have The Costume Kid in it.

Another theory is that the lost scripts are too obscene for human eyes and makes The Night at Its a Small World look like an award winning masterpiece compared to the scripts, though Gunner has insisted they are amazing.