Surprsising Chloe Sims on her 35th birthday, Mario made a return to TOWIE during Wednesday night's series finale and viewers could see that his locks have grown considerably.
The star, who originally quit the ITVBe show last year, has now revealed that he is growing his hair for a very special cause.
Pre-empting any mean comments about his new look, Mario Instagrammed a post that read: "Before some of you make nasty comments about my long locks of hair, I am growing it so I can donate it to Little Princess Trust next year. So please be nice, as I am doing something nice."
Little Princess Trust is a charity that provides wigs made of real hair to children suffering from hair loss. In May, One Direction star Harry Styles chopped off his long ponytail before donating it to the cause.
Rather than the mean comments he feared, like Harry, Mario has been inundated with support for his kind gesture. Fans have been quick to congratulate him, with one replying: "What a lovely thing to do, Mario." Another added: "I think the long hair suits you. Was good to see you on TOWIE last night."
After four years on the show, Mario quit TOWIE in 2015, saying: "I have had a great time on TOWIE and relished the many opportunities the show has given me but after 14 series, I feel it is time to move on and explore something new."
Last year, he briefly appeared in the Christmas special where he gave Billie Faiers' daughter Nelly a gift.
Following his big comeback on Wednesday night, Mario tweeted: "Couldn't miss the old goats birthday, could I @Chloe_Sims? Good to be back to Essex.. It's the only way."
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