The fashion designer, who left Essex behind in December to go backpacking with sister Georgia, spent her day quad biking before being treated to a birthday dinner.
Commenting on a photo posted to Instagram, Lydia said: "Not my average birthday party but the best one yet #Cambodia."
Lydia, who shares the same birthday with former TOWIE hunk Mark Wright, tweeted this morning: "All the best people were born today. Happy birthday @MarkWright_."
Plenty of past and present TOWIE stars have also sent Lydia birthday messages on Twitter. Ferne McCann wrote: "Happy Birthday @LydiaRoseBright have a lovely day and enjoy your travels. I'm jealous."
Meanwhile, Lauren Pope said: "A big Happy Birthday to @LydiaRoseBright hope you're enjoying your travels."
Elsewhere, former Made In Chelsea star Ashley James tweeted: "It might be your birthday but please stop making me jealous with your amazing photos @LydiaRoseBright! Happiest of birthdays beauty xxx."
But perhaps the cutest birthday message came from Lydia's mum, Debbie Douglas, who shared a childhood photo of Lydia from when she was a baby.
Debbie, who quit TOWIE in March last year, said: "Seems like yesterday I was kissing this face. Happy Birthday my darling @LydiaRoseBright love you duck face x."
Taking to Twitter, Lydia added: "Thanks everyone for my bday messages. Can't think of a better way to celebrate than quad biking through Siem Reap, Cambodia."
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