Lauren Pope, James 'Arg' Argent and Charlie Sims sent their support via Twitter as Mario entered the house on Thursday night (22 August) to a reception of boos, with Arg championing Mario to make "Essex proud".
Arg, who is currently partying in Marbella, made sure to send a shout-out to Mario. He said: "Good luck to @Mario_Falcone in #CBB He will do Essex proud...I hope! Lol x."
Lauren, who often nicknames Mario 'Marian', tweeted: "So I'm hearing Marian's gone in the CBB house, big good luck @Mario_Falcone #towiefamily."
Meanwhile, Charlie, who enjoyed a holiday to Ibiza with Mario last month, simply said: "Come on Maz! @Mario_Falcone!!!!," before asking his Twitter followers if Mario would beat reality show rival, Geordie Shore's Charlotte Crosby, who also entered the house last night.
Posing the question, Charlie asked: "Who will survive the longest, #GeordieShore @CharlotteGShore or #TOWIE @Mario_Falcone #BattleOfRealityStars #CBB #BigBrother."
Charlie has struck up quite a close bromance with Mario, and it definitely looks like he'll be missing the Italian tailor the most. This afternoon, after sharing a photo of himself with Mario, Charlie said: "Missing this guy already.. Good luck @mario_falcone #CelebBB."
Other good luck tweets came from Carol Wright, Tom Pearce and Frankie Essex, as well as former TOWIE star Lydia Bright and her mum Debbie Douglas, who admitted to being worried about Mario entering the house.
She tweeted: "My poor poor @Mario_Falcone will be eaten alive in the big brother house #CBB."
Meanwhile Mario's ex-girlfriend Lucy Mecklenburgh, who is currently in Los Angeles on business meetings, wrote a speculative tweet last night, saying: "Interesting... #CBB ... off for a lunch meeting at Chateau Marmont #LA."
While Mario's gone into the house, his sister Giovanna Fletcher has taken over his Twitter account to start drumming up support. Mario's brother-in-law and McFly vocalist Tom Fletcher, said: "Ok lets give our @Mario_Falcone some proper bro-in-law support and help him win #CBB!!!!!"
Meanwhile, former Waterloo Road actress Chelsee Healey, tweeted: "Well I think @Mario_Falcone looks nervous came across great tho!"
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Copyright: Channel 5