Harry, 19, beamed with delight as he arrived as a "special guest" to see his sister, Gemma Anne Styles, graduate at Sheffield Hallam University.
Gemma, who graduated with a first class honours degree in Science Education with Qualified Teacher Status, was cheered on by Harry and their mum, Anne on Wednesday afternoon (13 November).
Harry and Gemma later posed for a photo, which was posted to Harry's Instagram account.
Harry, who grinned and stuck his tongue out towards the camera, wrapped his arm around Gemma. Captioning the snap, he said: "My Sister graduated today. She's all clever and that."
Meanwhile, the university also posted photos from the special occasion on Twitter. One snap show Harry grinning as he sits down to watch the ceremony alongside his mum.
The university account tweeted: "A special guest attended today's graduation ceremony to see his sister collect her degree! Welcome @Harry_Styles."
In another snap, which shows an official graduation photo of the siblings, Sheffield Hallam University tweeted: "Congratulations to @GemmaAnneStyles on her degree and a warm Sheffield welcome to her brother @Harry_Styles too!"
Harry is currently on a well-deserved break after wrapping up 1D's mammoth 'Take Me Home' world tour in Japan last week (3 November).
Harry will be back on the road next year with his bandmates for their follow-up tour, 'Where We Are.'
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