The 'Live While We're Young' singer, who competed with his bandmates on The X Factor in 2010, is said to have told the Union J member that the secret to success lies in their matching curly hairstyles.
"Harry and George swapped numbers as the two groups are bound to start bumping into each other around the scene," a source told The Mirror.
"Harry sees a lot of himself in George, so wanted to pass on a jokey text revealing his own secret, which is why he told him to never cut his curls as he reckons his hair makes him such a hit with the ladies."
The insider continued: "George was laughing and showed the text to a couple of people, but I'd say there's no way he'll be going for any drastic haircuts from now on."
Shelley has been romantically linked to fellow X Factor contestant Ella Henderson since the live shows began, though she has denied the claims.
Photo gallery - The X Factor's second results show:
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