You won't believe the birthday present JK Rowling got from her son

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Harry Potter author JK Rowling still gets the odd naughty gift on her special day.

She shared this snap of the very un-child friendly gift her 13-year-old son David gave to her.

JK had lots to celebrate as she turned 51 - her play Harry Potter and the Cursed Child officially opened and has had rave reviews.

And just look at this magnificent cake she got!

She also scored a big cuddle from Noma Dumezweni, who plays the grown up Hermione in the play.

Happy birthday JK!