The 28-year-old former mole, who was today nominated to face the public vote after the Save & Replace competition, dropped the bombshell to a visibly stunned Shabby and Caoimhe.
"So you're the housemate with the secret?" exclaimed Shabby, referring to a pre-show tabloid rumour that one housemate would reveal a shocking secret about themselves in week six.
The duo continued to press Mario for information, repeating the housemates' suspicions that he was from royalty and asking whether the public are aware of the secret, to which Mario guessed they "probably" are.
Despite making Caoimhe and Shabby promise to keep his revelation secret, Mario let Josie in on the conversation when she came to join them in the bathroom.
"I reckon its something to do with your parents 'cause everytime I ask you about them you go, 'Yeah let's not talk about that'," she stated. "Are they famous, they are aren't they?"
"I'm not going to talk about that," replied Mario, which satisfied Josie that her prediction was correct. She then speculated that Mario was the son of Dolly Parton or "something to do with Al Capone".
Josie then spread the news to Ben, David, Steve and John James who agreed with her assumption that Mario has famous parents, eventually drawing the conclusion that he is the son of The Sopranos actor James Gandolfini. Thinking back to the rumour in the press, John James suggested that Mario's parents would enter the house in week six.
"You guys are so bloody paranoid," said a visibly agitated Mario. "Lets just pretend this was never brought up. I don’t have a secret."
"Secrets are good," agreed Ben, another housemate that has chosen to keep many details of his life outside the house a mystery. "I don’t want to know everything about his private life."