We received clarification from our

We received clarification from our KMart contact that they are not sure who was partnered with Harry during the floating feather scene because of how sooty they both look. The person assumed it was Neville due to him botching things but if you read the book and check out this HP Galleries analysis, Harry is partnered with Seamus Finnegan.

Harry’s partner was Seamus Finnigan (which was a relief, because Neville had been trying to catch his eye).

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It was very difficult. Harry and Seamus swished and flicked, but the feather they were supposed to be sending skyward just lay on the desktop. Seamus got so impatient that he prodded it with his wand and set fire to it — Harry had to put it out with his hat.

I think it’s safe to say that Seamus is partnered with Harry in this scene.