ITV Corrie fans confused by Summer's age as they mock birthday celebrations

Summer Spellman was celebrating a big birthday on Coronation Street as she turned 18. The troubled teen was treated to a slap-up meal for her special day by her three dads Billy Mayhew, Paul Foreman and Todd Grimshaw, and fans had plenty to say as she had a typically gloomy time on the cobbles.

Over her celebratory lunch at Speed Daal, Billy handed Summer a letter which her late dad Drew Spellman had asked him to give her on her 18th. Far from being thrilled, Summer was scared of opening the letter and ended up walking out on her lunch.

She was in for another unnerving surprise when Billy revealed to the diabetic teen that her nurse had called to confirm she was eligible for a glucose monitor. Summer was upset that Billy and her boyfriend Aaron Sandford had gone behind her back.

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After rowing with Aaron she met her friends at the cafe and was presented with a vegan carrot cake made for her by Nina Lucas. But the thoughtful treat failed to bring a smile to her face and she walked out again saying she was in no mood for a party.

Fans of the soap were left scratching their heads over her age including @Sally33903769 who remarked on Twitter about the balloons blunder that said she was '81': "Summer I think 81 was more accurate." @DanHarvey74 joked: "Summer's not having much fun on her 40th is she?" and @Willswhinge asked: "Summer is only 18? Then how come she always sounds like a miserable old woman?"

Meanwhile @laurenldugdale puzzled: "And if Aadi and Summer were doing their GCSEs together why isn’t Aadi 18? Unless he’s 18 by Wednesday?" and @littlesprite_ tweeted: "Summer is in the same year as Amy and